/* * Copyright (c) 1997, 2020, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_RUNTIME_GLOBALS_HPP #define SHARE_RUNTIME_GLOBALS_HPP #include "compiler/compiler_globals.hpp" #include "gc/shared/gc_globals.hpp" #include "runtime/globals_shared.hpp" #include "utilities/align.hpp" #include "utilities/globalDefinitions.hpp" #include "utilities/macros.hpp" #include CPU_HEADER(globals) #include OS_HEADER(globals) #include OS_CPU_HEADER(globals) // develop flags are settable / visible only during development and are constant in the PRODUCT version // product flags are always settable / visible // notproduct flags are settable / visible only during development and are not declared in the PRODUCT version // A flag must be declared with one of the following types: // bool, int, uint, intx, uintx, size_t, ccstr, ccstrlist, double, or uint64_t. // The type "ccstr" and "ccstrlist" are an alias for "const char*" and is used // only in this file, because the macrology requires single-token type names. // Note: Diagnostic options not meant for VM tuning or for product modes. // They are to be used for VM quality assurance or field diagnosis // of VM bugs. They are hidden so that users will not be encouraged to // try them as if they were VM ordinary execution options. However, they // are available in the product version of the VM. Under instruction // from support engineers, VM customers can turn them on to collect // diagnostic information about VM problems. To use a VM diagnostic // option, you must first specify +UnlockDiagnosticVMOptions. // (This master switch also affects the behavior of -Xprintflags.) // // experimental flags are in support of features that are not // part of the officially supported product, but are available // for experimenting with. They could, for example, be performance // features that may not have undergone full or rigorous QA, but which may // help performance in some cases and released for experimentation // by the community of users and developers. This flag also allows one to // be able to build a fully supported product that nonetheless also // ships with some unsupported, lightly tested, experimental features. // Like the UnlockDiagnosticVMOptions flag above, there is a corresponding // UnlockExperimentalVMOptions flag, which allows the control and // modification of the experimental flags. // // Nota bene: neither diagnostic nor experimental options should be used casually, // and they are not supported on production loads, except under explicit // direction from support engineers. // // manageable flags are writeable external product flags. // They are dynamically writeable through the JDK management interface // (com.sun.management.HotSpotDiagnosticMXBean API) and also through JConsole. // These flags are external exported interface (see CCC). The list of // manageable flags can be queried programmatically through the management // interface. // // A flag can be made as "manageable" only if // - the flag is defined in a CCC as an external exported interface. // - the VM implementation supports dynamic setting of the flag. // This implies that the VM must *always* query the flag variable // and not reuse state related to the flag state at any given time. // - you want the flag to be queried programmatically by the customers. // // product_rw flags are writeable internal product flags. // They are like "manageable" flags but for internal/private use. // The list of product_rw flags are internal/private flags which // may be changed/removed in a future release. It can be set // through the management interface to get/set value // when the name of flag is supplied. // // A flag can be made as "product_rw" only if // - the VM implementation supports dynamic setting of the flag. // This implies that the VM must *always* query the flag variable // and not reuse state related to the flag state at any given time. // // Note that when there is a need to support develop flags to be writeable, // it can be done in the same way as product_rw. // // range is a macro that will expand to min and max arguments for range // checking code if provided - see jvmFlagRangeList.hpp // // constraint is a macro that will expand to custom function call // for constraint checking if provided - see jvmFlagConstraintList.hpp // Default and minimum StringTable and SymbolTable size values // Must be powers of 2 const size_t defaultStringTableSize = NOT_LP64(1024) LP64_ONLY(65536); const size_t minimumStringTableSize = 128; const size_t defaultSymbolTableSize = 32768; // 2^15 const size_t minimumSymbolTableSize = 1024; #define RUNTIME_FLAGS(develop, \ develop_pd, \ product, \ product_pd, \ diagnostic, \ diagnostic_pd, \ experimental, \ notproduct, \ manageable, \ product_rw, \ lp64_product, \ range, \ constraint) \ \ lp64_product(bool, UseCompressedOops, false, \ "Use 32-bit object references in 64-bit VM. " \ "lp64_product means flag is always constant in 32 bit VM") \ \ lp64_product(bool, UseCompressedClassPointers, false, \ "Use 32-bit class pointers in 64-bit VM. " \ "lp64_product means flag is always constant in 32 bit VM") \ \ notproduct(bool, CheckCompressedOops, true, \ "Generate checks in encoding/decoding code in debug VM") \ \ product(uintx, HeapSearchSteps, 3 PPC64_ONLY(+17), \ "Heap allocation steps through preferred address regions to find" \ " where it can allocate the heap. Number of steps to take per " \ "region.") \ range(1, max_uintx) \ \ lp64_product(intx, ObjectAlignmentInBytes, 8, \ "Default object alignment in bytes, 8 is minimum") \ range(8, 256) \ constraint(ObjectAlignmentInBytesConstraintFunc,AtParse) \ \ develop(bool, CleanChunkPoolAsync, true, \ "Clean the chunk pool asynchronously") \ \ diagnostic(uint, HandshakeTimeout, 0, \ "If nonzero set a timeout in milliseconds for handshakes") \ \ experimental(bool, AlwaysSafeConstructors, false, \ "Force safe construction, as if all fields are final.") \ \ diagnostic(bool, UnlockDiagnosticVMOptions, trueInDebug, \ "Enable normal processing of flags relating to field diagnostics")\ \ experimental(bool, UnlockExperimentalVMOptions, false, \ "Enable normal processing of flags relating to experimental " \ "features") \ \ product(bool, JavaMonitorsInStackTrace, true, \ "Print information about Java monitor locks when the stacks are" \ "dumped") \ \ product_pd(bool, UseLargePages, \ "Use large page memory") \ \ product_pd(bool, UseLargePagesIndividualAllocation, \ "Allocate large pages individually for better affinity") \ \ develop(bool, LargePagesIndividualAllocationInjectError, false, \ "Fail large pages individual allocation") \ \ product(bool, UseLargePagesInMetaspace, false, \ "(Deprecated) Use large page memory in metaspace. " \ "Only used if UseLargePages is enabled.") \ \ product(bool, UseNUMA, false, \ "Use NUMA if available") \ \ product(bool, UseNUMAInterleaving, false, \ "Interleave memory across NUMA nodes if available") \ \ product(size_t, NUMAInterleaveGranularity, 2*M, \ "Granularity to use for NUMA interleaving on Windows OS") \ range(os::vm_allocation_granularity(), NOT_LP64(2*G) LP64_ONLY(8192*G)) \ \ product(bool, ForceNUMA, false, \ "(Deprecated) Force NUMA optimizations on single-node/UMA systems") \ \ product(uintx, NUMAChunkResizeWeight, 20, \ "Percentage (0-100) used to weight the current sample when " \ "computing exponentially decaying average for " \ "AdaptiveNUMAChunkSizing") \ range(0, 100) \ \ product(size_t, NUMASpaceResizeRate, 1*G, \ "Do not reallocate more than this amount per collection") \ range(0, max_uintx) \ \ product(bool, UseAdaptiveNUMAChunkSizing, true, \ "Enable adaptive chunk sizing for NUMA") \ \ product(bool, NUMAStats, false, \ "Print NUMA stats in detailed heap information") \ \ product(uintx, NUMAPageScanRate, 256, \ "Maximum number of pages to include in the page scan procedure") \ range(0, max_uintx) \ \ product(bool, UseAES, false, \ "Control whether AES instructions are used when available") \ \ product(bool, UseFMA, false, \ "Control whether FMA instructions are used when available") \ \ product(bool, UseSHA, false, \ "Control whether SHA instructions are used when available") \ \ diagnostic(bool, UseGHASHIntrinsics, false, \ "Use intrinsics for GHASH versions of crypto") \ \ product(bool, UseBASE64Intrinsics, false, \ "Use intrinsics for java.util.Base64") \ \ product(size_t, LargePageSizeInBytes, 0, \ "Large page size (0 to let VM choose the page size)") \ range(0, max_uintx) \ \ product(size_t, LargePageHeapSizeThreshold, 128*M, \ "Use large pages if maximum heap is at least this big") \ range(0, max_uintx) \ \ product(bool, ForceTimeHighResolution, false, \ "Using high time resolution (for Win32 only)") \ \ develop(bool, TracePcPatching, false, \ "Trace usage of frame::patch_pc") \ \ develop(bool, TraceRelocator, false, \ "Trace the bytecode relocator") \ \ develop(bool, TraceLongCompiles, false, \ "Print out every time compilation is longer than " \ "a given threshold") \ \ diagnostic(bool, SafepointALot, false, \ "Generate a lot of safepoints. This works with " \ "GuaranteedSafepointInterval") \ \ diagnostic(bool, HandshakeALot, false, \ "Generate a lot of handshakes. This works with " \ "GuaranteedSafepointInterval") \ \ product_pd(bool, BackgroundCompilation, \ "A thread requesting compilation is not blocked during " \ "compilation") \ \ product(bool, MethodFlushing, true, \ "Reclamation of zombie and not-entrant methods") \ \ develop(bool, VerifyStack, false, \ "Verify stack of each thread when it is entering a runtime call") \ \ diagnostic(bool, ForceUnreachable, false, \ "Make all non code cache addresses to be unreachable by " \ "forcing use of 64bit literal fixups") \ \ notproduct(bool, StressDerivedPointers, false, \ "Force scavenge when a derived pointer is detected on stack " \ "after rtm call") \ \ develop(bool, TraceDerivedPointers, false, \ "Trace traversal of derived pointers on stack") \ \ notproduct(bool, TraceCodeBlobStacks, false, \ "Trace stack-walk of codeblobs") \ \ notproduct(bool, PrintRewrites, false, \ "Print methods that are being rewritten") \ \ product(bool, UseInlineCaches, true, \ "Use Inline Caches for virtual calls ") \ \ diagnostic(bool, InlineArrayCopy, true, \ "Inline arraycopy native that is known to be part of " \ "base library DLL") \ \ diagnostic(bool, InlineObjectHash, true, \ "Inline Object::hashCode() native that is known to be part " \ "of base library DLL") \ \ diagnostic(bool, InlineNatives, true, \ "Inline natives that are known to be part of base library DLL") \ \ diagnostic(bool, InlineMathNatives, true, \ "Inline SinD, CosD, etc.") \ \ diagnostic(bool, InlineClassNatives, true, \ "Inline Class.isInstance, etc") \ \ diagnostic(bool, InlineThreadNatives, true, \ "Inline Thread.currentThread, etc") \ \ diagnostic(bool, InlineUnsafeOps, true, \ "Inline memory ops (native methods) from Unsafe") \ \ product(bool, CriticalJNINatives, true, \ "Check for critical JNI entry points") \ \ notproduct(bool, StressCriticalJNINatives, false, \ "Exercise register saving code in critical natives") \ \ diagnostic(bool, UseAESIntrinsics, false, \ "Use intrinsics for AES versions of crypto") \ \ diagnostic(bool, UseAESCTRIntrinsics, false, \ "Use intrinsics for the paralleled version of AES/CTR crypto") \ \ diagnostic(bool, UseSHA1Intrinsics, false, \ "Use intrinsics for SHA-1 crypto hash function. " \ "Requires that UseSHA is enabled.") \ \ diagnostic(bool, UseSHA256Intrinsics, false, \ "Use intrinsics for SHA-224 and SHA-256 crypto hash functions. " \ "Requires that UseSHA is enabled.") \ \ diagnostic(bool, UseSHA512Intrinsics, false, \ "Use intrinsics for SHA-384 and SHA-512 crypto hash functions. " \ "Requires that UseSHA is enabled.") \ \ diagnostic(bool, UseCRC32Intrinsics, false, \ "use intrinsics for java.util.zip.CRC32") \ \ diagnostic(bool, UseCRC32CIntrinsics, false, \ "use intrinsics for java.util.zip.CRC32C") \ \ diagnostic(bool, UseAdler32Intrinsics, false, \ "use intrinsics for java.util.zip.Adler32") \ \ diagnostic(bool, UseVectorizedMismatchIntrinsic, false, \ "Enables intrinsification of ArraysSupport.vectorizedMismatch()") \ \ diagnostic(ccstrlist, DisableIntrinsic, "", \ "do not expand intrinsics whose (internal) names appear here") \ \ diagnostic(ccstrlist, ControlIntrinsic, "", \ "Control intrinsics using a list of +/- (internal) names, " \ "separated by commas") \ \ develop(bool, TraceCallFixup, false, \ "Trace all call fixups") \ \ develop(bool, DeoptimizeALot, false, \ "Deoptimize at every exit from the runtime system") \ \ notproduct(ccstrlist, DeoptimizeOnlyAt, "", \ "A comma separated list of bcis to deoptimize at") \ \ develop(bool, DeoptimizeRandom, false, \ "Deoptimize random frames on random exit from the runtime system")\ \ notproduct(bool, ZombieALot, false, \ "Create zombies (non-entrant) at exit from the runtime system") \ \ notproduct(bool, WalkStackALot, false, \ "Trace stack (no print) at every exit from the runtime system") \ \ product(bool, Debugging, false, \ "Set when executing debug methods in debug.cpp " \ "(to prevent triggering assertions)") \ \ notproduct(bool, VerifyLastFrame, false, \ "Verify oops on last frame on entry to VM") \ \ product(bool, SafepointTimeout, false, \ "Time out and warn or fail after SafepointTimeoutDelay " \ "milliseconds if failed to reach safepoint") \ \ diagnostic(bool, AbortVMOnSafepointTimeout, false, \ "Abort upon failure to reach safepoint (see SafepointTimeout)") \ \ diagnostic(bool, AbortVMOnVMOperationTimeout, false, \ "Abort upon failure to complete VM operation promptly") \ \ diagnostic(intx, AbortVMOnVMOperationTimeoutDelay, 1000, \ "Delay in milliseconds for option AbortVMOnVMOperationTimeout") \ range(0, max_intx) \ \ /* 50 retries * (5 * current_retry_count) millis = ~6.375 seconds */ \ /* typically, at most a few retries are needed */ \ product(intx, SuspendRetryCount, 50, \ "Maximum retry count for an external suspend request") \ range(0, max_intx) \ \ product(intx, SuspendRetryDelay, 5, \ "Milliseconds to delay per retry (* current_retry_count)") \ range(0, max_intx) \ \ product(bool, AssertOnSuspendWaitFailure, false, \ "Assert/Guarantee on external suspend wait failure") \ \ product(bool, TraceSuspendWaitFailures, false, \ "Trace external suspend wait failures") \ \ product(bool, MaxFDLimit, true, \ "Bump the number of file descriptors to maximum (Unix only)") \ \ diagnostic(bool, LogEvents, true, \ "Enable the various ring buffer event logs") \ \ diagnostic(uintx, LogEventsBufferEntries, 20, \ "Number of ring buffer event logs") \ range(1, NOT_LP64(1*K) LP64_ONLY(1*M)) \ \ diagnostic(bool, BytecodeVerificationRemote, true, \ "Enable the Java bytecode verifier for remote classes") \ \ diagnostic(bool, BytecodeVerificationLocal, false, \ "Enable the Java bytecode verifier for local classes") \ \ develop(bool, ForceFloatExceptions, trueInDebug, \ "Force exceptions on FP stack under/overflow") \ \ develop(bool, VerifyStackAtCalls, false, \ "Verify that the stack pointer is unchanged after calls") \ \ develop(bool, TraceJavaAssertions, false, \ "Trace java language assertions") \ \ notproduct(bool, VerifyCodeCache, false, \ "Verify code cache on memory allocation/deallocation") \ \ develop(bool, UseMallocOnly, false, \ "Use only malloc/free for allocation (no resource area/arena)") \ \ develop(bool, ZapResourceArea, trueInDebug, \ "Zap freed resource/arena space with 0xABABABAB") \ \ notproduct(bool, ZapVMHandleArea, trueInDebug, \ "Zap freed VM handle space with 0xBCBCBCBC") \ \ notproduct(bool, ZapStackSegments, trueInDebug, \ "Zap allocated/freed stack segments with 0xFADFADED") \ \ develop(bool, ZapUnusedHeapArea, trueInDebug, \ "Zap unused heap space with 0xBAADBABE") \ \ develop(bool, CheckZapUnusedHeapArea, false, \ "Check zapping of unused heap space") \ \ develop(bool, ZapFillerObjects, trueInDebug, \ "Zap filler objects with 0xDEAFBABE") \ \ develop(bool, PrintVMMessages, true, \ "Print VM messages on console") \ \ notproduct(uintx, ErrorHandlerTest, 0, \ "If > 0, provokes an error after VM initialization; the value " \ "determines which error to provoke. See test_error_handler() " \ "in vmError.cpp.") \ \ notproduct(uintx, TestCrashInErrorHandler, 0, \ "If > 0, provokes an error inside VM error handler (a secondary " \ "crash). see test_error_handler() in vmError.cpp") \ \ notproduct(bool, TestSafeFetchInErrorHandler, false, \ "If true, tests SafeFetch inside error handler.") \ \ notproduct(bool, TestUnresponsiveErrorHandler, false, \ "If true, simulates an unresponsive error handler.") \ \ develop(bool, Verbose, false, \ "Print additional debugging information from other modes") \ \ develop(bool, PrintMiscellaneous, false, \ "Print uncategorized debugging information (requires +Verbose)") \ \ develop(bool, WizardMode, false, \ "Print much more debugging information") \ \ product(bool, ShowMessageBoxOnError, false, \ "Keep process alive on VM fatal error") \ \ product(bool, CreateCoredumpOnCrash, true, \ "Create core/mini dump on VM fatal error") \ \ product(uint64_t, ErrorLogTimeout, 2 * 60, \ "Timeout, in seconds, to limit the time spent on writing an " \ "error log in case of a crash.") \ range(0, (uint64_t)max_jlong/1000) \ \ product_pd(bool, UseOSErrorReporting, \ "Let VM fatal error propagate to the OS (ie. WER on Windows)") \ \ product(bool, SuppressFatalErrorMessage, false, \ "Report NO fatal error message (avoid deadlock)") \ \ product(ccstrlist, OnError, "", \ "Run user-defined commands on fatal error; see VMError.cpp " \ "for examples") \ \ product(ccstrlist, OnOutOfMemoryError, "", \ "Run user-defined commands on first java.lang.OutOfMemoryError") \ \ manageable(bool, HeapDumpBeforeFullGC, false, \ "Dump heap to file before any major stop-the-world GC") \ \ manageable(bool, HeapDumpAfterFullGC, false, \ "Dump heap to file after any major stop-the-world GC") \ \ manageable(bool, HeapDumpOnOutOfMemoryError, false, \ "Dump heap to file when java.lang.OutOfMemoryError is thrown") \ \ manageable(ccstr, HeapDumpPath, NULL, \ "When HeapDumpOnOutOfMemoryError is on, the path (filename or " \ "directory) of the dump file (defaults to java_pid.hprof " \ "in the working directory)") \ \ develop(bool, BreakAtWarning, false, \ "Execute breakpoint upon encountering VM warning") \ \ product(ccstr, NativeMemoryTracking, "off", \ "Native memory tracking options") \ \ diagnostic(bool, PrintNMTStatistics, false, \ "Print native memory tracking summary data if it is on") \ \ diagnostic(bool, LogCompilation, false, \ "Log compilation activity in detail to LogFile") \ \ product(bool, PrintCompilation, false, \ "Print compilations") \ \ product(bool, PrintExtendedThreadInfo, false, \ "Print more information in thread dump") \ \ diagnostic(intx, ScavengeRootsInCode, 2, \ "0: do not allow scavengable oops in the code cache; " \ "1: allow scavenging from the code cache; " \ "2: emit as many constants as the compiler can see") \ range(0, 2) \ \ product(bool, AlwaysRestoreFPU, false, \ "Restore the FPU control word after every JNI call (expensive)") \ \ diagnostic(bool, PrintCompilation2, false, \ "Print additional statistics per compilation") \ \ diagnostic(bool, PrintAdapterHandlers, false, \ "Print code generated for i2c/c2i adapters") \ \ diagnostic(bool, VerifyAdapterCalls, trueInDebug, \ "Verify that i2c/c2i adapters are called properly") \ \ develop(bool, VerifyAdapterSharing, false, \ "Verify that the code for shared adapters is the equivalent") \ \ diagnostic(bool, PrintAssembly, false, \ "Print assembly code (using external disassembler.so)") \ \ diagnostic(ccstr, PrintAssemblyOptions, NULL, \ "Print options string passed to disassembler.so") \ \ notproduct(bool, PrintNMethodStatistics, false, \ "Print a summary statistic for the generated nmethods") \ \ diagnostic(bool, PrintNMethods, false, \ "Print assembly code for nmethods when generated") \ \ diagnostic(bool, PrintNativeNMethods, false, \ "Print assembly code for native nmethods when generated") \ \ develop(bool, PrintDebugInfo, false, \ "Print debug information for all nmethods when generated") \ \ develop(bool, PrintRelocations, false, \ "Print relocation information for all nmethods when generated") \ \ develop(bool, PrintDependencies, false, \ "Print dependency information for all nmethods when generated") \ \ develop(bool, PrintExceptionHandlers, false, \ "Print exception handler tables for all nmethods when generated") \ \ develop(bool, StressCompiledExceptionHandlers, false, \ "Exercise compiled exception handlers") \ \ develop(bool, InterceptOSException, false, \ "Start debugger when an implicit OS (e.g. NULL) " \ "exception happens") \ \ product(bool, PrintCodeCache, false, \ "Print the code cache memory usage when exiting") \ \ develop(bool, PrintCodeCache2, false, \ "Print detailed usage information on the code cache when exiting")\ \ product(bool, PrintCodeCacheOnCompilation, false, \ "Print the code cache memory usage each time a method is " \ "compiled") \ \ diagnostic(bool, PrintCodeHeapAnalytics, false, \ "Print code heap usage statistics on exit and on full condition") \ \ diagnostic(bool, PrintStubCode, false, \ "Print generated stub code") \ \ product(bool, StackTraceInThrowable, true, \ "Collect backtrace in throwable when exception happens") \ \ product(bool, OmitStackTraceInFastThrow, true, \ "Omit backtraces for some 'hot' exceptions in optimized code") \ \ manageable(bool, ShowCodeDetailsInExceptionMessages, true, \ "Show exception messages from RuntimeExceptions that contain " \ "snippets of the failing code. Disable this to improve privacy.") \ \ product(bool, PrintWarnings, true, \ "Print JVM warnings to output stream") \ \ notproduct(uintx, WarnOnStalledSpinLock, 0, \ "Print warnings for stalled SpinLocks") \ \ product(bool, RegisterFinalizersAtInit, true, \ "Register finalizable objects at end of Object. or " \ "after allocation") \ \ develop(bool, RegisterReferences, true, \ "Tell whether the VM should register soft/weak/final/phantom " \ "references") \ \ develop(bool, IgnoreRewrites, false, \ "Suppress rewrites of bytecodes in the oopmap generator. " \ "This is unsafe!") \ \ develop(bool, PrintCodeCacheExtension, false, \ "Print extension of code cache") \ \ develop(bool, UsePrivilegedStack, true, \ "Enable the security JVM functions") \ \ develop(bool, ProtectionDomainVerification, true, \ "Verify protection domain before resolution in system dictionary")\ \ product(bool, ClassUnloading, true, \ "Do unloading of classes") \ \ product(bool, ClassUnloadingWithConcurrentMark, true, \ "Do unloading of classes with a concurrent marking cycle") \ \ develop(bool, DisableStartThread, false, \ "Disable starting of additional Java threads " \ "(for debugging only)") \ \ develop(bool, MemProfiling, false, \ "Write memory usage profiling to log file") \ \ notproduct(bool, PrintSystemDictionaryAtExit, false, \ "Print the system dictionary at exit") \ \ diagnostic(bool, DynamicallyResizeSystemDictionaries, true, \ "Dynamically resize system dictionaries as needed") \ \ product(bool, AlwaysLockClassLoader, false, \ "Require the VM to acquire the class loader lock before calling " \ "loadClass() even for class loaders registering " \ "as parallel capable") \ \ product(bool, AllowParallelDefineClass, false, \ "Allow parallel defineClass requests for class loaders " \ "registering as parallel capable") \ \ product_pd(bool, DontYieldALot, \ "Throw away obvious excess yield calls") \ \ experimental(bool, DisablePrimordialThreadGuardPages, false, \ "Disable the use of stack guard pages if the JVM is loaded " \ "on the primordial process thread") \ \ /* notice: the max range value here is max_jint, not max_intx */ \ /* because of overflow issue */ \ diagnostic(intx, AsyncDeflationInterval, 250, \ "Async deflate idle monitors every so many milliseconds when " \ "MonitorUsedDeflationThreshold is exceeded (0 is off).") \ range(0, max_jint) \ \ experimental(intx, MonitorUsedDeflationThreshold, 90, \ "Percentage of used monitors before triggering deflation (0 is " \ "off). The check is performed on GuaranteedSafepointInterval " \ "or AsyncDeflationInterval.") \ range(0, 100) \ \ experimental(intx, hashCode, 5, \ "(Unstable) select hashCode generation algorithm") \ \ product(bool, FilterSpuriousWakeups, true, \ "When true prevents OS-level spurious, or premature, wakeups " \ "from Object.wait (Ignored for Windows)") \ \ product(bool, ReduceSignalUsage, false, \ "Reduce the use of OS signals in Java and/or the VM") \ \ develop(bool, LoadLineNumberTables, true, \ "Tell whether the class file parser loads line number tables") \ \ develop(bool, LoadLocalVariableTables, true, \ "Tell whether the class file parser loads local variable tables") \ \ develop(bool, LoadLocalVariableTypeTables, true, \ "Tell whether the class file parser loads local variable type" \ "tables") \ \ product(bool, AllowUserSignalHandlers, false, \ "Do not complain if the application installs signal handlers " \ "(Unix only)") \ \ product(bool, UseSignalChaining, true, \ "Use signal-chaining to invoke signal handlers installed " \ "by the application (Unix only)") \ \ product(bool, RestoreMXCSROnJNICalls, false, \ "Restore MXCSR when returning from JNI calls") \ \ product(bool, CheckJNICalls, false, \ "Verify all arguments to JNI calls") \ \ product(bool, UseFastJNIAccessors, true, \ "Use optimized versions of GetField") \ \ product(intx, MaxJNILocalCapacity, 65536, \ "Maximum allowable local JNI handle capacity to " \ "EnsureLocalCapacity() and PushLocalFrame(), " \ "where <= 0 is unlimited, default: 65536") \ range(min_intx, max_intx) \ \ product(bool, EagerXrunInit, false, \ "Eagerly initialize -Xrun libraries; allows startup profiling, " \ "but not all -Xrun libraries may support the state of the VM " \ "at this time") \ \ product(bool, PreserveAllAnnotations, false, \ "Preserve RuntimeInvisibleAnnotations as well " \ "as RuntimeVisibleAnnotations") \ \ develop(uintx, PreallocatedOutOfMemoryErrorCount, 4, \ "Number of OutOfMemoryErrors preallocated with backtrace") \ \ product(bool, UseXMMForArrayCopy, false, \ "Use SSE2 MOVQ instruction for Arraycopy") \ \ notproduct(bool, PrintFieldLayout, false, \ "Print field layout for each class") \ \ /* Need to limit the extent of the padding to reasonable size. */\ /* 8K is well beyond the reasonable HW cache line size, even with */\ /* aggressive prefetching, while still leaving the room for segregating */\ /* among the distinct pages. */\ product(intx, ContendedPaddingWidth, 128, \ "How many bytes to pad the fields/classes marked @Contended with")\ range(0, 8192) \ constraint(ContendedPaddingWidthConstraintFunc,AfterErgo) \ \ product(bool, EnableContended, true, \ "Enable @Contended annotation support") \ \ product(bool, RestrictContended, true, \ "Restrict @Contended to trusted classes") \ \ product(bool, UseBiasedLocking, false, \ "(Deprecated) Enable biased locking in JVM") \ \ product(intx, BiasedLockingStartupDelay, 0, \ "(Deprecated) Number of milliseconds to wait before enabling " \ "biased locking") \ range(0, (intx)(max_jint-(max_jint%PeriodicTask::interval_gran))) \ constraint(BiasedLockingStartupDelayFunc,AfterErgo) \ \ diagnostic(bool, PrintBiasedLockingStatistics, false, \ "(Deprecated) Print statistics of biased locking in JVM") \ \ product(intx, BiasedLockingBulkRebiasThreshold, 20, \ "(Deprecated) Threshold of number of revocations per type to " \ "try to rebias all objects in the heap of that type") \ range(0, max_intx) \ constraint(BiasedLockingBulkRebiasThresholdFunc,AfterErgo) \ \ product(intx, BiasedLockingBulkRevokeThreshold, 40, \ "(Deprecated) Threshold of number of revocations per type to " \ "permanently revoke biases of all objects in the heap of that " \ "type") \ range(0, max_intx) \ constraint(BiasedLockingBulkRevokeThresholdFunc,AfterErgo) \ \ product(intx, BiasedLockingDecayTime, 25000, \ "(Deprecated) Decay time (in milliseconds) to re-enable bulk " \ "rebiasing of a type after previous bulk rebias") \ range(500, max_intx) \ constraint(BiasedLockingDecayTimeFunc,AfterErgo) \ \ product(bool, ExitOnOutOfMemoryError, false, \ "JVM exits on the first occurrence of an out-of-memory error") \ \ product(bool, CrashOnOutOfMemoryError, false, \ "JVM aborts, producing an error log and core/mini dump, on the " \ "first occurrence of an out-of-memory error") \ \ /* tracing */ \ \ develop(bool, StressRewriter, false, \ "Stress linktime bytecode rewriting") \ \ product(ccstr, TraceJVMTI, NULL, \ "Trace flags for JVMTI functions and events") \ \ /* This option can change an EMCP method into an obsolete method. */ \ /* This can affect tests that except specific methods to be EMCP. */ \ /* This option should be used with caution. */ \ product(bool, StressLdcRewrite, false, \ "Force ldc -> ldc_w rewrite during RedefineClasses") \ \ /* change to false by default sometime after Mustang */ \ product(bool, VerifyMergedCPBytecodes, true, \ "Verify bytecodes after RedefineClasses constant pool merging") \ \ product(bool, AllowRedefinitionToAddDeleteMethods, false, \ "(Deprecated) Allow redefinition to add and delete private " \ "static or final methods for compatibility with old releases") \ \ develop(bool, TraceBytecodes, false, \ "Trace bytecode execution") \ \ develop(bool, TraceICs, false, \ "Trace inline cache changes") \ \ notproduct(bool, TraceInvocationCounterOverflow, false, \ "Trace method invocation counter overflow") \ \ develop(bool, TraceInlineCacheClearing, false, \ "Trace clearing of inline caches in nmethods") \ \ develop(bool, TraceDependencies, false, \ "Trace dependencies") \ \ develop(bool, VerifyDependencies, trueInDebug, \ "Exercise and verify the compilation dependency mechanism") \ \ develop(bool, TraceNewOopMapGeneration, false, \ "Trace OopMapGeneration") \ \ develop(bool, TraceNewOopMapGenerationDetailed, false, \ "Trace OopMapGeneration: print detailed cell states") \ \ develop(bool, TimeOopMap, false, \ "Time calls to GenerateOopMap::compute_map() in sum") \ \ develop(bool, TimeOopMap2, false, \ "Time calls to GenerateOopMap::compute_map() individually") \ \ develop(bool, TraceOopMapRewrites, false, \ "Trace rewriting of method oops during oop map generation") \ \ develop(bool, TraceICBuffer, false, \ "Trace usage of IC buffer") \ \ develop(bool, TraceCompiledIC, false, \ "Trace changes of compiled IC") \ \ develop(bool, FLSVerifyDictionary, false, \ "Do lots of (expensive) FLS dictionary verification") \ \ \ notproduct(bool, CheckMemoryInitialization, false, \ "Check memory initialization") \ \ product(uintx, ProcessDistributionStride, 4, \ "Stride through processors when distributing processes") \ range(0, max_juint) \ \ develop(bool, TraceFinalizerRegistration, false, \ "Trace registration of final references") \ \ product(bool, IgnoreEmptyClassPaths, false, \ "Ignore empty path elements in -classpath") \ \ product(size_t, InitialBootClassLoaderMetaspaceSize, \ NOT_LP64(2200*K) LP64_ONLY(4*M), \ "(Deprecated) Initial size of the boot class loader data metaspace") \ range(30*K, max_uintx/BytesPerWord) \ constraint(InitialBootClassLoaderMetaspaceSizeConstraintFunc, AfterErgo)\ \ product(bool, PrintHeapAtSIGBREAK, true, \ "Print heap layout in response to SIGBREAK") \ \ manageable(bool, PrintClassHistogram, false, \ "Print a histogram of class instances") \ \ experimental(double, ObjectCountCutOffPercent, 0.5, \ "The percentage of the used heap that the instances of a class " \ "must occupy for the class to generate a trace event") \ range(0.0, 100.0) \ \ /* JVMTI heap profiling */ \ \ diagnostic(bool, TraceJVMTIObjectTagging, false, \ "Trace JVMTI object tagging calls") \ \ diagnostic(bool, VerifyBeforeIteration, false, \ "Verify memory system before JVMTI iteration") \ \ /* compiler interface */ \ \ develop(bool, CIPrintCompilerName, false, \ "when CIPrint is active, print the name of the active compiler") \ \ diagnostic(bool, CIPrintCompileQueue, false, \ "display the contents of the compile queue whenever a " \ "compilation is enqueued") \ \ develop(bool, CIPrintRequests, false, \ "display every request for compilation") \ \ product(bool, CITime, false, \ "collect timing information for compilation") \ \ develop(bool, CITimeVerbose, false, \ "be more verbose in compilation timings") \ \ develop(bool, CITimeEach, false, \ "display timing information after each successful compilation") \ \ develop(bool, CICountOSR, false, \ "use a separate counter when assigning ids to osr compilations") \ \ develop(bool, CICompileNatives, true, \ "compile native methods if supported by the compiler") \ \ develop_pd(bool, CICompileOSR, \ "compile on stack replacement methods if supported by the " \ "compiler") \ \ develop(bool, CIPrintMethodCodes, false, \ "print method bytecodes of the compiled code") \ \ develop(bool, CIPrintTypeFlow, false, \ "print the results of ciTypeFlow analysis") \ \ develop(bool, CITraceTypeFlow, false, \ "detailed per-bytecode tracing of ciTypeFlow analysis") \ \ develop(intx, OSROnlyBCI, -1, \ "OSR only at this bci. Negative values mean exclude that bci") \ \ /* compiler */ \ \ /* notice: the max range value here is max_jint, not max_intx */ \ /* because of overflow issue */ \ product(intx, CICompilerCount, CI_COMPILER_COUNT, \ "Number of compiler threads to run") \ range(0, max_jint) \ constraint(CICompilerCountConstraintFunc, AfterErgo) \ \ product(bool, UseDynamicNumberOfCompilerThreads, true, \ "Dynamically choose the number of parallel compiler threads") \ \ diagnostic(bool, ReduceNumberOfCompilerThreads, true, \ "Reduce the number of parallel compiler threads when they " \ "are not used") \ \ diagnostic(bool, TraceCompilerThreads, false, \ "Trace creation and removal of compiler threads") \ \ develop(bool, InjectCompilerCreationFailure, false, \ "Inject thread creation failures for " \ "UseDynamicNumberOfCompilerThreads") \ \ develop(bool, UseStackBanging, true, \ "use stack banging for stack overflow checks (required for " \ "proper StackOverflow handling; disable only to measure cost " \ "of stackbanging)") \ \ develop(bool, GenerateSynchronizationCode, true, \ "generate locking/unlocking code for synchronized methods and " \ "monitors") \ \ develop(bool, GenerateRangeChecks, true, \ "Generate range checks for array accesses") \ \ diagnostic_pd(bool, ImplicitNullChecks, \ "Generate code for implicit null checks") \ \ product_pd(bool, TrapBasedNullChecks, \ "Generate code for null checks that uses a cmp and trap " \ "instruction raising SIGTRAP. This is only used if an access to" \ "null (+offset) will not raise a SIGSEGV, i.e.," \ "ImplicitNullChecks don't work (PPC64).") \ \ diagnostic(bool, EnableThreadSMRExtraValidityChecks, true, \ "Enable Thread SMR extra validity checks") \ \ diagnostic(bool, EnableThreadSMRStatistics, trueInDebug, \ "Enable Thread SMR Statistics") \ \ product(bool, UseNotificationThread, true, \ "Use Notification Thread") \ \ product(bool, Inline, true, \ "Enable inlining") \ \ product(bool, ClipInlining, true, \ "Clip inlining if aggregate method exceeds DesiredMethodLimit") \ \ develop(bool, UseCHA, true, \ "Enable CHA") \ \ product(bool, UseTypeProfile, true, \ "Check interpreter profile for historically monomorphic calls") \ \ diagnostic(bool, PrintInlining, false, \ "Print inlining optimizations") \ \ product(bool, UsePopCountInstruction, false, \ "Use population count instruction") \ \ develop(bool, EagerInitialization, false, \ "Eagerly initialize classes if possible") \ \ diagnostic(bool, LogTouchedMethods, false, \ "Log methods which have been ever touched in runtime") \ \ diagnostic(bool, PrintTouchedMethodsAtExit, false, \ "Print all methods that have been ever touched in runtime") \ \ develop(bool, TraceMethodReplacement, false, \ "Print when methods are replaced do to recompilation") \ \ develop(bool, PrintMethodFlushing, false, \ "Print the nmethods being flushed") \ \ diagnostic(bool, PrintMethodFlushingStatistics, false, \ "print statistics about method flushing") \ \ diagnostic(intx, HotMethodDetectionLimit, 100000, \ "Number of compiled code invocations after which " \ "the method is considered as hot by the flusher") \ range(1, max_jint) \ \ diagnostic(intx, MinPassesBeforeFlush, 10, \ "Minimum number of sweeper passes before an nmethod " \ "can be flushed") \ range(0, max_intx) \ \ product(bool, UseCodeAging, true, \ "Insert counter to detect warm methods") \ \ diagnostic(bool, StressCodeAging, false, \ "Start with counters compiled in") \ \ develop(bool, StressCodeBuffers, false, \ "Exercise code buffer expansion and other rare state changes") \ \ diagnostic(bool, DebugNonSafepoints, trueInDebug, \ "Generate extra debugging information for non-safepoints in " \ "nmethods") \ \ product(bool, PrintVMOptions, false, \ "Print flags that appeared on the command line") \ \ product(bool, IgnoreUnrecognizedVMOptions, false, \ "Ignore unrecognized VM options") \ \ product(bool, PrintCommandLineFlags, false, \ "Print flags specified on command line or set by ergonomics") \ \ product(bool, PrintFlagsInitial, false, \ "Print all VM flags before argument processing and exit VM") \ \ product(bool, PrintFlagsFinal, false, \ "Print all VM flags after argument and ergonomic processing") \ \ notproduct(bool, PrintFlagsWithComments, false, \ "Print all VM flags with default values and descriptions and " \ "exit") \ \ product(bool, PrintFlagsRanges, false, \ "Print VM flags and their ranges") \ \ diagnostic(bool, SerializeVMOutput, true, \ "Use a mutex to serialize output to tty and LogFile") \ \ diagnostic(bool, DisplayVMOutput, true, \ "Display all VM output on the tty, independently of LogVMOutput") \ \ diagnostic(bool, LogVMOutput, false, \ "Save VM output to LogFile") \ \ diagnostic(ccstr, LogFile, NULL, \ "If LogVMOutput or LogCompilation is on, save VM output to " \ "this file [default: ./hotspot_pid%p.log] (%p replaced with pid)")\ \ product(ccstr, ErrorFile, NULL, \ "If an error occurs, save the error data to this file " \ "[default: ./hs_err_pid%p.log] (%p replaced with pid)") \ \ product(bool, ExtensiveErrorReports, \ PRODUCT_ONLY(false) NOT_PRODUCT(true), \ "Error reports are more extensive.") \ \ product(bool, DisplayVMOutputToStderr, false, \ "If DisplayVMOutput is true, display all VM output to stderr") \ \ product(bool, DisplayVMOutputToStdout, false, \ "If DisplayVMOutput is true, display all VM output to stdout") \ \ product(bool, ErrorFileToStderr, false, \ "If true, error data is printed to stderr instead of a file") \ \ product(bool, ErrorFileToStdout, false, \ "If true, error data is printed to stdout instead of a file") \ \ product(bool, UseHeavyMonitors, false, \ "use heavyweight instead of lightweight Java monitors") \ \ product(bool, PrintStringTableStatistics, false, \ "print statistics about the StringTable and SymbolTable") \ \ diagnostic(bool, VerifyStringTableAtExit, false, \ "verify StringTable contents at exit") \ \ notproduct(bool, PrintSymbolTableSizeHistogram, false, \ "print histogram of the symbol table") \ \ notproduct(bool, ExitVMOnVerifyError, false, \ "standard exit from VM if bytecode verify error " \ "(only in debug mode)") \ \ diagnostic(ccstr, AbortVMOnException, NULL, \ "Call fatal if this exception is thrown. Example: " \ "java -XX:AbortVMOnException=java.lang.NullPointerException Foo") \ \ diagnostic(ccstr, AbortVMOnExceptionMessage, NULL, \ "Call fatal if the exception pointed by AbortVMOnException " \ "has this message") \ \ develop(bool, DebugVtables, false, \ "add debugging code to vtable dispatch") \ \ notproduct(bool, PrintVtableStats, false, \ "print vtables stats at end of run") \ \ develop(bool, TraceCreateZombies, false, \ "trace creation of zombie nmethods") \ \ product(bool, RangeCheckElimination, true, \ "Eliminate range checks") \ \ develop_pd(bool, UncommonNullCast, \ "track occurrences of null in casts; adjust compiler tactics") \ \ develop(bool, TypeProfileCasts, true, \ "treat casts like calls for purposes of type profiling") \ \ develop(bool, TraceLivenessGen, false, \ "Trace the generation of liveness analysis information") \ \ notproduct(bool, TraceLivenessQuery, false, \ "Trace queries of liveness analysis information") \ \ notproduct(bool, CollectIndexSetStatistics, false, \ "Collect information about IndexSets") \ \ develop(bool, UseLoopSafepoints, true, \ "Generate Safepoint nodes in every loop") \ \ develop(intx, FastAllocateSizeLimit, 128*K, \ /* Note: This value is zero mod 1<<13 for a cheap sparc set. */ \ "Inline allocations larger than this in doublewords must go slow")\ \ product_pd(bool, CompactStrings, \ "Enable Strings to use single byte chars in backing store") \ \ product_pd(uintx, TypeProfileLevel, \ "=XYZ, with Z: Type profiling of arguments at call; " \ "Y: Type profiling of return value at call; " \ "X: Type profiling of parameters to methods; " \ "X, Y and Z in 0=off ; 1=jsr292 only; 2=all methods") \ constraint(TypeProfileLevelConstraintFunc, AfterErgo) \ \ product(intx, TypeProfileArgsLimit, 2, \ "max number of call arguments to consider for type profiling") \ range(0, 16) \ \ product(intx, TypeProfileParmsLimit, 2, \ "max number of incoming parameters to consider for type profiling"\ ", -1 for all") \ range(-1, 64) \ \ /* statistics */ \ develop(bool, CountCompiledCalls, false, \ "Count method invocations") \ \ notproduct(bool, CountRuntimeCalls, false, \ "Count VM runtime calls") \ \ develop(bool, CountJNICalls, false, \ "Count jni method invocations") \ \ notproduct(bool, CountJVMCalls, false, \ "Count jvm method invocations") \ \ notproduct(bool, CountRemovableExceptions, false, \ "Count exceptions that could be replaced by branches due to " \ "inlining") \ \ notproduct(bool, ICMissHistogram, false, \ "Produce histogram of IC misses") \ \ /* interpreter */ \ product_pd(bool, RewriteBytecodes, \ "Allow rewriting of bytecodes (bytecodes are not immutable)") \ \ product_pd(bool, RewriteFrequentPairs, \ "Rewrite frequently used bytecode pairs into a single bytecode") \ \ diagnostic(bool, PrintInterpreter, false, \ "Print the generated interpreter code") \ \ product(bool, UseInterpreter, true, \ "Use interpreter for non-compiled methods") \ \ develop(bool, UseFastSignatureHandlers, true, \ "Use fast signature handlers for native calls") \ \ product(bool, UseLoopCounter, true, \ "Increment invocation counter on backward branch") \ \ product_pd(bool, UseOnStackReplacement, \ "Use on stack replacement, calls runtime if invoc. counter " \ "overflows in loop") \ \ notproduct(bool, TraceOnStackReplacement, false, \ "Trace on stack replacement") \ \ product_pd(bool, PreferInterpreterNativeStubs, \ "Use always interpreter stubs for native methods invoked via " \ "interpreter") \ \ develop(bool, CountBytecodes, false, \ "Count number of bytecodes executed") \ \ develop(bool, PrintBytecodeHistogram, false, \ "Print histogram of the executed bytecodes") \ \ develop(bool, PrintBytecodePairHistogram, false, \ "Print histogram of the executed bytecode pairs") \ \ diagnostic(bool, PrintSignatureHandlers, false, \ "Print code generated for native method signature handlers") \ \ develop(bool, VerifyOops, false, \ "Do plausibility checks for oops") \ \ develop(bool, CheckUnhandledOops, false, \ "Check for unhandled oops in VM code") \ \ develop(bool, VerifyJNIFields, trueInDebug, \ "Verify jfieldIDs for instance fields") \ \ notproduct(bool, VerifyJNIEnvThread, false, \ "Verify JNIEnv.thread == Thread::current() when entering VM " \ "from JNI") \ \ develop(bool, VerifyFPU, false, \ "Verify FPU state (check for NaN's, etc.)") \ \ develop(bool, VerifyThread, false, \ "Watch the thread register for corruption (SPARC only)") \ \ develop(bool, VerifyActivationFrameSize, false, \ "Verify that activation frame didn't become smaller than its " \ "minimal size") \ \ develop(bool, TraceFrequencyInlining, false, \ "Trace frequency based inlining") \ \ develop_pd(bool, InlineIntrinsics, \ "Inline intrinsics that can be statically resolved") \ \ product_pd(bool, ProfileInterpreter, \ "Profile at the bytecode level during interpretation") \ \ develop(bool, TraceProfileInterpreter, false, \ "Trace profiling at the bytecode level during interpretation. " \ "This outputs the profiling information collected to improve " \ "jit compilation.") \ \ develop_pd(bool, ProfileTraps, \ "Profile deoptimization traps at the bytecode level") \ \ product(intx, ProfileMaturityPercentage, 20, \ "number of method invocations/branches (expressed as % of " \ "CompileThreshold) before using the method's profile") \ range(0, 100) \ \ diagnostic(bool, PrintMethodData, false, \ "Print the results of +ProfileInterpreter at end of run") \ \ develop(bool, VerifyDataPointer, trueInDebug, \ "Verify the method data pointer during interpreter profiling") \ \ develop(bool, VerifyCompiledCode, false, \ "Include miscellaneous runtime verifications in nmethod code; " \ "default off because it disturbs nmethod size heuristics") \ \ notproduct(bool, CrashGCForDumpingJavaThread, false, \ "Manually make GC thread crash then dump java stack trace; " \ "Test only") \ \ /* compilation */ \ product(bool, UseCompiler, true, \ "Use Just-In-Time compilation") \ \ product(bool, UseCounterDecay, true, \ "Adjust recompilation counters") \ \ develop(intx, CounterHalfLifeTime, 30, \ "Half-life time of invocation counters (in seconds)") \ \ develop(intx, CounterDecayMinIntervalLength, 500, \ "The minimum interval (in milliseconds) between invocation of " \ "CounterDecay") \ \ product(bool, AlwaysCompileLoopMethods, false, \ "When using recompilation, never interpret methods " \ "containing loops") \ \ product(bool, DontCompileHugeMethods, true, \ "Do not compile methods > HugeMethodLimit") \ \ /* Bytecode escape analysis estimation. */ \ product(bool, EstimateArgEscape, true, \ "Analyze bytecodes to estimate escape state of arguments") \ \ product(intx, BCEATraceLevel, 0, \ "How much tracing to do of bytecode escape analysis estimates " \ "(0-3)") \ range(0, 3) \ \ product(intx, MaxBCEAEstimateLevel, 5, \ "Maximum number of nested calls that are analyzed by BC EA") \ range(0, max_jint) \ \ product(intx, MaxBCEAEstimateSize, 150, \ "Maximum bytecode size of a method to be analyzed by BC EA") \ range(0, max_jint) \ \ product(intx, AllocatePrefetchStyle, 1, \ "0 = no prefetch, " \ "1 = generate prefetch instructions for each allocation, " \ "2 = use TLAB watermark to gate allocation prefetch, " \ "3 = generate one prefetch instruction per cache line") \ range(0, 3) \ \ product(intx, AllocatePrefetchDistance, -1, \ "Distance to prefetch ahead of allocation pointer. " \ "-1: use system-specific value (automatically determined") \ constraint(AllocatePrefetchDistanceConstraintFunc,AfterMemoryInit)\ \ product(intx, AllocatePrefetchLines, 3, \ "Number of lines to prefetch ahead of array allocation pointer") \ range(1, 64) \ \ product(intx, AllocateInstancePrefetchLines, 1, \ "Number of lines to prefetch ahead of instance allocation " \ "pointer") \ range(1, 64) \ \ product(intx, AllocatePrefetchStepSize, 16, \ "Step size in bytes of sequential prefetch instructions") \ range(1, 512) \ constraint(AllocatePrefetchStepSizeConstraintFunc,AfterMemoryInit)\ \ product(intx, AllocatePrefetchInstr, 0, \ "Select instruction to prefetch ahead of allocation pointer") \ constraint(AllocatePrefetchInstrConstraintFunc, AfterMemoryInit) \ \ /* deoptimization */ \ develop(bool, TraceDeoptimization, false, \ "Trace deoptimization") \ \ develop(bool, PrintDeoptimizationDetails, false, \ "Print more information about deoptimization") \ \ develop(bool, DebugDeoptimization, false, \ "Tracing various information while debugging deoptimization") \ \ product(intx, SelfDestructTimer, 0, \ "Will cause VM to terminate after a given time (in minutes) " \ "(0 means off)") \ range(0, max_intx) \ \ product(intx, MaxJavaStackTraceDepth, 1024, \ "The maximum number of lines in the stack trace for Java " \ "exceptions (0 means all)") \ range(0, max_jint/2) \ \ /* notice: the max range value here is max_jint, not max_intx */ \ /* because of overflow issue */ \ diagnostic(intx, GuaranteedSafepointInterval, 1000, \ "Guarantee a safepoint (at least) every so many milliseconds " \ "(0 means none)") \ range(0, max_jint) \ \ product(intx, SafepointTimeoutDelay, 10000, \ "Delay in milliseconds for option SafepointTimeout") \ LP64_ONLY(range(0, max_intx/MICROUNITS)) \ NOT_LP64(range(0, max_intx)) \ \ product(intx, NmethodSweepActivity, 10, \ "Removes cold nmethods from code cache if > 0. Higher values " \ "result in more aggressive sweeping") \ range(0, 2000) \ \ notproduct(bool, LogSweeper, false, \ "Keep a ring buffer of sweeper activity") \ \ notproduct(intx, SweeperLogEntries, 1024, \ "Number of records in the ring buffer of sweeper activity") \ \ notproduct(intx, MemProfilingInterval, 500, \ "Time between each invocation of the MemProfiler") \ \ develop(intx, MallocCatchPtr, -1, \ "Hit breakpoint when mallocing/freeing this pointer") \ \ notproduct(ccstrlist, SuppressErrorAt, "", \ "List of assertions (file:line) to muzzle") \ \ develop(intx, StackPrintLimit, 100, \ "number of stack frames to print in VM-level stack dump") \ \ notproduct(intx, MaxElementPrintSize, 256, \ "maximum number of elements to print") \ \ notproduct(intx, MaxSubklassPrintSize, 4, \ "maximum number of subklasses to print when printing klass") \ \ develop(intx, MaxForceInlineLevel, 100, \ "maximum number of nested calls that are forced for inlining " \ "(using CompileCommand or marked w/ @ForceInline)") \ range(0, max_jint) \ \ product(intx, MinInliningThreshold, 250, \ "The minimum invocation count a method needs to have to be " \ "inlined") \ range(0, max_jint) \ \ develop(intx, MethodHistogramCutoff, 100, \ "The cutoff value for method invocation histogram (+CountCalls)") \ \ develop(intx, DontYieldALotInterval, 10, \ "Interval between which yields will be dropped (milliseconds)") \ \ notproduct(intx, DeoptimizeALotInterval, 5, \ "Number of exits until DeoptimizeALot kicks in") \ \ notproduct(intx, ZombieALotInterval, 5, \ "Number of exits until ZombieALot kicks in") \ \ diagnostic(uintx, MallocMaxTestWords, 0, \ "If non-zero, maximum number of words that malloc/realloc can " \ "allocate (for testing only)") \ range(0, max_uintx) \ \ product(intx, TypeProfileWidth, 2, \ "Number of receiver types to record in call/cast profile") \ range(0, 8) \ \ develop(intx, BciProfileWidth, 2, \ "Number of return bci's to record in ret profile") \ \ product(intx, PerMethodRecompilationCutoff, 400, \ "After recompiling N times, stay in the interpreter (-1=>'Inf')") \ range(-1, max_intx) \ \ product(intx, PerBytecodeRecompilationCutoff, 200, \ "Per-BCI limit on repeated recompilation (-1=>'Inf')") \ range(-1, max_intx) \ \ product(intx, PerMethodTrapLimit, 100, \ "Limit on traps (of one kind) in a method (includes inlines)") \ range(0, max_jint) \ \ experimental(intx, PerMethodSpecTrapLimit, 5000, \ "Limit on speculative traps (of one kind) in a method " \ "(includes inlines)") \ range(0, max_jint) \ \ product(intx, PerBytecodeTrapLimit, 4, \ "Limit on traps (of one kind) at a particular BCI") \ range(0, max_jint) \ \ experimental(intx, SpecTrapLimitExtraEntries, 3, \ "Extra method data trap entries for speculation") \ \ develop(intx, InlineFrequencyRatio, 20, \ "Ratio of call site execution to caller method invocation") \ range(0, max_jint) \ \ diagnostic_pd(intx, InlineFrequencyCount, \ "Count of call site execution necessary to trigger frequent " \ "inlining") \ range(0, max_jint) \ \ develop(intx, InlineThrowCount, 50, \ "Force inlining of interpreted methods that throw this often") \ range(0, max_jint) \ \ develop(intx, InlineThrowMaxSize, 200, \ "Force inlining of throwing methods smaller than this") \ range(0, max_jint) \ \ develop(intx, ProfilerNodeSize, 1024, \ "Size in K to allocate for the Profile Nodes of each thread") \ range(0, 1024) \ \ product_pd(size_t, MetaspaceSize, \ "Initial threshold (in bytes) at which a garbage collection " \ "is done to reduce Metaspace usage") \ constraint(MetaspaceSizeConstraintFunc,AfterErgo) \ \ product(size_t, MaxMetaspaceSize, max_uintx, \ "Maximum size of Metaspaces (in bytes)") \ constraint(MaxMetaspaceSizeConstraintFunc,AfterErgo) \ \ product(size_t, CompressedClassSpaceSize, 1*G, \ "Maximum size of class area in Metaspace when compressed " \ "class pointers are used") \ range(1*M, 3*G) \ \ manageable(uintx, MinHeapFreeRatio, 40, \ "The minimum percentage of heap free after GC to avoid expansion."\ " For most GCs this applies to the old generation. In G1 and" \ " ParallelGC it applies to the whole heap.") \ range(0, 100) \ constraint(MinHeapFreeRatioConstraintFunc,AfterErgo) \ \ manageable(uintx, MaxHeapFreeRatio, 70, \ "The maximum percentage of heap free after GC to avoid shrinking."\ " For most GCs this applies to the old generation. In G1 and" \ " ParallelGC it applies to the whole heap.") \ range(0, 100) \ constraint(MaxHeapFreeRatioConstraintFunc,AfterErgo) \ \ product(bool, ShrinkHeapInSteps, true, \ "When disabled, informs the GC to shrink the java heap directly" \ " to the target size at the next full GC rather than requiring" \ " smaller steps during multiple full GCs.") \ \ product(intx, SoftRefLRUPolicyMSPerMB, 1000, \ "Number of milliseconds per MB of free space in the heap") \ range(0, max_intx) \ constraint(SoftRefLRUPolicyMSPerMBConstraintFunc,AfterMemoryInit) \ \ product(size_t, MinHeapDeltaBytes, ScaleForWordSize(128*K), \ "The minimum change in heap space due to GC (in bytes)") \ range(0, max_uintx) \ \ product(size_t, MinMetaspaceExpansion, ScaleForWordSize(256*K), \ "The minimum expansion of Metaspace (in bytes)") \ range(0, max_uintx) \ \ product(uintx, MaxMetaspaceFreeRatio, 70, \ "The maximum percentage of Metaspace free after GC to avoid " \ "shrinking") \ range(0, 100) \ constraint(MaxMetaspaceFreeRatioConstraintFunc,AfterErgo) \ \ product(uintx, MinMetaspaceFreeRatio, 40, \ "The minimum percentage of Metaspace free after GC to avoid " \ "expansion") \ range(0, 99) \ constraint(MinMetaspaceFreeRatioConstraintFunc,AfterErgo) \ \ product(size_t, MaxMetaspaceExpansion, ScaleForWordSize(4*M), \ "The maximum expansion of Metaspace without full GC (in bytes)") \ range(0, max_uintx) \ \ /* stack parameters */ \ product_pd(intx, StackYellowPages, \ "Number of yellow zone (recoverable overflows) pages of size " \ "4KB. If pages are bigger yellow zone is aligned up.") \ range(MIN_STACK_YELLOW_PAGES, (DEFAULT_STACK_YELLOW_PAGES+5)) \ \ product_pd(intx, StackRedPages, \ "Number of red zone (unrecoverable overflows) pages of size " \ "4KB. If pages are bigger red zone is aligned up.") \ range(MIN_STACK_RED_PAGES, (DEFAULT_STACK_RED_PAGES+2)) \ \ product_pd(intx, StackReservedPages, \ "Number of reserved zone (reserved to annotated methods) pages" \ " of size 4KB. If pages are bigger reserved zone is aligned up.") \ range(MIN_STACK_RESERVED_PAGES, (DEFAULT_STACK_RESERVED_PAGES+10))\ \ product(bool, RestrictReservedStack, true, \ "Restrict @ReservedStackAccess to trusted classes") \ \ /* greater stack shadow pages can't generate instruction to bang stack */ \ product_pd(intx, StackShadowPages, \ "Number of shadow zone (for overflow checking) pages of size " \ "4KB. If pages are bigger shadow zone is aligned up. " \ "This should exceed the depth of the VM and native call stack.") \ range(MIN_STACK_SHADOW_PAGES, (DEFAULT_STACK_SHADOW_PAGES+30)) \ \ product_pd(intx, ThreadStackSize, \ "Thread Stack Size (in Kbytes)") \ range(0, 1 * M) \ \ product_pd(intx, VMThreadStackSize, \ "Non-Java Thread Stack Size (in Kbytes)") \ range(0, max_intx/(1 * K)) \ \ product_pd(intx, CompilerThreadStackSize, \ "Compiler Thread Stack Size (in Kbytes)") \ range(0, max_intx/(1 * K)) \ \ develop_pd(size_t, JVMInvokeMethodSlack, \ "Stack space (bytes) required for JVM_InvokeMethod to complete") \ \ /* code cache parameters */ \ develop_pd(uintx, CodeCacheSegmentSize, \ "Code cache segment size (in bytes) - smallest unit of " \ "allocation") \ range(1, 1024) \ constraint(CodeCacheSegmentSizeConstraintFunc, AfterErgo) \ \ develop_pd(intx, CodeEntryAlignment, \ "Code entry alignment for generated code (in bytes)") \ constraint(CodeEntryAlignmentConstraintFunc, AfterErgo) \ \ product_pd(intx, OptoLoopAlignment, \ "Align inner loops to zero relative to this modulus") \ range(1, 16) \ constraint(OptoLoopAlignmentConstraintFunc, AfterErgo) \ \ product_pd(uintx, InitialCodeCacheSize, \ "Initial code cache size (in bytes)") \ range(os::vm_page_size(), max_uintx) \ \ develop_pd(uintx, CodeCacheMinimumUseSpace, \ "Minimum code cache size (in bytes) required to start VM.") \ range(0, max_uintx) \ \ product(bool, SegmentedCodeCache, false, \ "Use a segmented code cache") \ \ product_pd(uintx, ReservedCodeCacheSize, \ "Reserved code cache size (in bytes) - maximum code cache size") \ range(os::vm_page_size(), max_uintx) \ \ product_pd(uintx, NonProfiledCodeHeapSize, \ "Size of code heap with non-profiled methods (in bytes)") \ range(0, max_uintx) \ \ product_pd(uintx, ProfiledCodeHeapSize, \ "Size of code heap with profiled methods (in bytes)") \ range(0, max_uintx) \ \ product_pd(uintx, NonNMethodCodeHeapSize, \ "Size of code heap with non-nmethods (in bytes)") \ range(os::vm_page_size(), max_uintx) \ \ product_pd(uintx, CodeCacheExpansionSize, \ "Code cache expansion size (in bytes)") \ range(32*K, max_uintx) \ \ diagnostic_pd(uintx, CodeCacheMinBlockLength, \ "Minimum number of segments in a code cache block") \ range(1, 100) \ \ notproduct(bool, ExitOnFullCodeCache, false, \ "Exit the VM if we fill the code cache") \ \ product(bool, UseCodeCacheFlushing, true, \ "Remove cold/old nmethods from the code cache") \ \ product(double, SweeperThreshold, 0.5, \ "Threshold controlling when code cache sweeper is invoked." \ "Value is percentage of ReservedCodeCacheSize.") \ range(0.0, 100.0) \ \ product(uintx, StartAggressiveSweepingAt, 10, \ "Start aggressive sweeping if X[%] of the code cache is free." \ "Segmented code cache: X[%] of the non-profiled heap." \ "Non-segmented code cache: X[%] of the total code cache") \ range(0, 100) \ \ /* AOT parameters */ \ experimental(bool, UseAOT, false, \ "Use AOT compiled files") \ \ experimental(ccstrlist, AOTLibrary, NULL, \ "AOT library") \ \ experimental(bool, PrintAOT, false, \ "Print used AOT klasses and methods") \ \ notproduct(bool, PrintAOTStatistics, false, \ "Print AOT statistics") \ \ diagnostic(bool, UseAOTStrictLoading, false, \ "Exit the VM if any of the AOT libraries has invalid config") \ \ product(bool, CalculateClassFingerprint, false, \ "Calculate class fingerprint") \ \ /* interpreter debugging */ \ develop(intx, BinarySwitchThreshold, 5, \ "Minimal number of lookupswitch entries for rewriting to binary " \ "switch") \ \ develop(intx, StopInterpreterAt, 0, \ "Stop interpreter execution at specified bytecode number") \ \ develop(intx, TraceBytecodesAt, 0, \ "Trace bytecodes starting with specified bytecode number") \ \ /* compiler interface */ \ develop(intx, CIStart, 0, \ "The id of the first compilation to permit") \ \ develop(intx, CIStop, max_jint, \ "The id of the last compilation to permit") \ \ develop(intx, CIStartOSR, 0, \ "The id of the first osr compilation to permit " \ "(CICountOSR must be on)") \ \ develop(intx, CIStopOSR, max_jint, \ "The id of the last osr compilation to permit " \ "(CICountOSR must be on)") \ \ develop(intx, CIBreakAtOSR, -1, \ "The id of osr compilation to break at") \ \ develop(intx, CIBreakAt, -1, \ "The id of compilation to break at") \ \ product(ccstrlist, CompileOnly, "", \ "List of methods (pkg/class.name) to restrict compilation to") \ \ product(ccstr, CompileCommandFile, NULL, \ "Read compiler commands from this file [.hotspot_compiler]") \ \ diagnostic(ccstr, CompilerDirectivesFile, NULL, \ "Read compiler directives from this file") \ \ product(ccstrlist, CompileCommand, "", \ "Prepend to .hotspot_compiler; e.g. log,java/lang/String.") \ \ develop(bool, ReplayCompiles, false, \ "Enable replay of compilations from ReplayDataFile") \ \ product(ccstr, ReplayDataFile, NULL, \ "File containing compilation replay information" \ "[default: ./replay_pid%p.log] (%p replaced with pid)") \ \ product(ccstr, InlineDataFile, NULL, \ "File containing inlining replay information" \ "[default: ./inline_pid%p.log] (%p replaced with pid)") \ \ develop(intx, ReplaySuppressInitializers, 2, \ "Control handling of class initialization during replay: " \ "0 - don't do anything special; " \ "1 - treat all class initializers as empty; " \ "2 - treat class initializers for application classes as empty; " \ "3 - allow all class initializers to run during bootstrap but " \ " pretend they are empty after starting replay") \ range(0, 3) \ \ develop(bool, ReplayIgnoreInitErrors, false, \ "Ignore exceptions thrown during initialization for replay") \ \ product(bool, DumpReplayDataOnError, true, \ "Record replay data for crashing compiler threads") \ \ product(bool, CICompilerCountPerCPU, false, \ "1 compiler thread for log(N CPUs)") \ \ notproduct(intx, CICrashAt, -1, \ "id of compilation to trigger assert in compiler thread for " \ "the purpose of testing, e.g. generation of replay data") \ notproduct(bool, CIObjectFactoryVerify, false, \ "enable potentially expensive verification in ciObjectFactory") \ \ diagnostic(bool, AbortVMOnCompilationFailure, false, \ "Abort VM when method had failed to compile.") \ \ /* Priorities */ \ product_pd(bool, UseThreadPriorities, "Use native thread priorities") \ \ product(intx, ThreadPriorityPolicy, 0, \ "0 : Normal. "\ " VM chooses priorities that are appropriate for normal "\ " applications. "\ " On Windows applications are allowed to use higher native "\ " priorities. However, with ThreadPriorityPolicy=0, VM will "\ " not use the highest possible native priority, "\ " THREAD_PRIORITY_TIME_CRITICAL, as it may interfere with "\ " system threads. On Linux thread priorities are ignored "\ " because the OS does not support static priority in "\ " SCHED_OTHER scheduling class which is the only choice for "\ " non-root, non-realtime applications. "\ "1 : Aggressive. "\ " Java thread priorities map over to the entire range of "\ " native thread priorities. Higher Java thread priorities map "\ " to higher native thread priorities. This policy should be "\ " used with care, as sometimes it can cause performance "\ " degradation in the application and/or the entire system. On "\ " Linux/BSD/macOS this policy requires root privilege or an "\ " extended capability.") \ range(0, 1) \ \ product(bool, ThreadPriorityVerbose, false, \ "Print priority changes") \ \ product(intx, CompilerThreadPriority, -1, \ "The native priority at which compiler threads should run " \ "(-1 means no change)") \ range(min_jint, max_jint) \ \ product(intx, VMThreadPriority, -1, \ "The native priority at which the VM thread should run " \ "(-1 means no change)") \ range(-1, 127) \ \ product(intx, JavaPriority1_To_OSPriority, -1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ product(intx, JavaPriority2_To_OSPriority, -1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ product(intx, JavaPriority3_To_OSPriority, -1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ product(intx, JavaPriority4_To_OSPriority, -1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ product(intx, JavaPriority5_To_OSPriority, -1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ product(intx, JavaPriority6_To_OSPriority, -1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ product(intx, JavaPriority7_To_OSPriority, -1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ product(intx, JavaPriority8_To_OSPriority, -1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ product(intx, JavaPriority9_To_OSPriority, -1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ product(intx, JavaPriority10_To_OSPriority,-1, \ "Map Java priorities to OS priorities") \ range(-1, 127) \ \ experimental(bool, UseCriticalJavaThreadPriority, false, \ "Java thread priority 10 maps to critical scheduling priority") \ \ experimental(bool, UseCriticalCompilerThreadPriority, false, \ "Compiler thread(s) run at critical scheduling priority") \ \ develop(intx, NewCodeParameter, 0, \ "Testing Only: Create a dedicated integer parameter before " \ "putback") \ \ /* new oopmap storage allocation */ \ develop(intx, MinOopMapAllocation, 8, \ "Minimum number of OopMap entries in an OopMapSet") \ \ /* Background Compilation */ \ develop(intx, LongCompileThreshold, 50, \ "Used with +TraceLongCompiles") \ \ /* recompilation */ \ product_pd(intx, CompileThreshold, \ "number of interpreted method invocations before (re-)compiling") \ constraint(CompileThresholdConstraintFunc, AfterErgo) \ \ product(double, CompileThresholdScaling, 1.0, \ "Factor to control when first compilation happens " \ "(both with and without tiered compilation): " \ "values greater than 1.0 delay counter overflow, " \ "values between 0 and 1.0 rush counter overflow, " \ "value of 1.0 leaves compilation thresholds unchanged " \ "value of 0.0 is equivalent to -Xint. " \ "" \ "Flag can be set as per-method option. " \ "If a value is specified for a method, compilation thresholds " \ "for that method are scaled by both the value of the global flag "\ "and the value of the per-method flag.") \ range(0.0, DBL_MAX) \ \ product(intx, Tier0InvokeNotifyFreqLog, 7, \ "Interpreter (tier 0) invocation notification frequency") \ range(0, 30) \ \ product(intx, Tier2InvokeNotifyFreqLog, 11, \ "C1 without MDO (tier 2) invocation notification frequency") \ range(0, 30) \ \ product(intx, Tier3InvokeNotifyFreqLog, 10, \ "C1 with MDO profiling (tier 3) invocation notification " \ "frequency") \ range(0, 30) \ \ product(intx, Tier23InlineeNotifyFreqLog, 20, \ "Inlinee invocation (tiers 2 and 3) notification frequency") \ range(0, 30) \ \ product(intx, Tier0BackedgeNotifyFreqLog, 10, \ "Interpreter (tier 0) invocation notification frequency") \ range(0, 30) \ \ product(intx, Tier2BackedgeNotifyFreqLog, 14, \ "C1 without MDO (tier 2) invocation notification frequency") \ range(0, 30) \ \ product(intx, Tier3BackedgeNotifyFreqLog, 13, \ "C1 with MDO profiling (tier 3) invocation notification " \ "frequency") \ range(0, 30) \ \ product(intx, Tier2CompileThreshold, 0, \ "threshold at which tier 2 compilation is invoked") \ range(0, max_jint) \ \ product(intx, Tier2BackEdgeThreshold, 0, \ "Back edge threshold at which tier 2 compilation is invoked") \ range(0, max_jint) \ \ product(intx, Tier3InvocationThreshold, 200, \ "Compile if number of method invocations crosses this " \ "threshold") \ range(0, max_jint) \ \ product(intx, Tier3MinInvocationThreshold, 100, \ "Minimum invocation to compile at tier 3") \ range(0, max_jint) \ \ product(intx, Tier3CompileThreshold, 2000, \ "Threshold at which tier 3 compilation is invoked (invocation " \ "minimum must be satisfied)") \ range(0, max_jint) \ \ product(intx, Tier3BackEdgeThreshold, 60000, \ "Back edge threshold at which tier 3 OSR compilation is invoked") \ range(0, max_jint) \ \ product(intx, Tier3AOTInvocationThreshold, 10000, \ "Compile if number of method invocations crosses this " \ "threshold if coming from AOT") \ range(0, max_jint) \ \ product(intx, Tier3AOTMinInvocationThreshold, 1000, \ "Minimum invocation to compile at tier 3 if coming from AOT") \ range(0, max_jint) \ \ product(intx, Tier3AOTCompileThreshold, 15000, \ "Threshold at which tier 3 compilation is invoked (invocation " \ "minimum must be satisfied) if coming from AOT") \ range(0, max_jint) \ \ product(intx, Tier3AOTBackEdgeThreshold, 120000, \ "Back edge threshold at which tier 3 OSR compilation is invoked " \ "if coming from AOT") \ range(0, max_jint) \ \ diagnostic(intx, Tier0AOTInvocationThreshold, 200, \ "Switch to interpreter to profile if the number of method " \ "invocations crosses this threshold if coming from AOT " \ "(applicable only with " \ "CompilationMode=high-only|high-only-quick-internal)") \ range(0, max_jint) \ \ diagnostic(intx, Tier0AOTMinInvocationThreshold, 100, \ "Minimum number of invocations to switch to interpreter " \ "to profile if coming from AOT " \ "(applicable only with " \ "CompilationMode=high-only|high-only-quick-internal)") \ range(0, max_jint) \ \ diagnostic(intx, Tier0AOTCompileThreshold, 2000, \ "Threshold at which to switch to interpreter to profile " \ "if coming from AOT " \ "(invocation minimum must be satisfied, " \ "applicable only with " \ "CompilationMode=high-only|high-only-quick-internal)") \ range(0, max_jint) \ \ diagnostic(intx, Tier0AOTBackEdgeThreshold, 60000, \ "Back edge threshold at which to switch to interpreter " \ "to profile if coming from AOT " \ "(applicable only with " \ "CompilationMode=high-only|high-only-quick-internal)") \ range(0, max_jint) \ \ product(intx, Tier4InvocationThreshold, 5000, \ "Compile if number of method invocations crosses this " \ "threshold") \ range(0, max_jint) \ \ product(intx, Tier4MinInvocationThreshold, 600, \ "Minimum invocation to compile at tier 4") \ range(0, max_jint) \ \ product(intx, Tier4CompileThreshold, 15000, \ "Threshold at which tier 4 compilation is invoked (invocation " \ "minimum must be satisfied)") \ range(0, max_jint) \ \ product(intx, Tier4BackEdgeThreshold, 40000, \ "Back edge threshold at which tier 4 OSR compilation is invoked") \ range(0, max_jint) \ \ diagnostic(intx, Tier40InvocationThreshold, 5000, \ "Compile if number of method invocations crosses this " \ "threshold (applicable only with " \ "CompilationMode=high-only|high-only-quick-internal)") \ range(0, max_jint) \ \ diagnostic(intx, Tier40MinInvocationThreshold, 600, \ "Minimum number of invocations to compile at tier 4 " \ "(applicable only with " \ "CompilationMode=high-only|high-only-quick-internal)") \ range(0, max_jint) \ \ diagnostic(intx, Tier40CompileThreshold, 10000, \ "Threshold at which tier 4 compilation is invoked (invocation " \ "minimum must be satisfied, applicable only with " \ "CompilationMode=high-only|high-only-quick-internal)") \ range(0, max_jint) \ \ diagnostic(intx, Tier40BackEdgeThreshold, 15000, \ "Back edge threshold at which tier 4 OSR compilation is invoked " \ "(applicable only with " \ "CompilationMode=high-only|high-only-quick-internal)") \ range(0, max_jint) \ \ diagnostic(intx, Tier0Delay, 5, \ "If C2 queue size grows over this amount per compiler thread " \ "do not start profiling in the interpreter " \ "(applicable only with " \ "CompilationMode=high-only|high-only-quick-internal)") \ range(0, max_jint) \ \ product(intx, Tier3DelayOn, 5, \ "If C2 queue size grows over this amount per compiler thread " \ "stop compiling at tier 3 and start compiling at tier 2") \ range(0, max_jint) \ \ product(intx, Tier3DelayOff, 2, \ "If C2 queue size is less than this amount per compiler thread " \ "allow methods compiled at tier 2 transition to tier 3") \ range(0, max_jint) \ \ product(intx, Tier3LoadFeedback, 5, \ "Tier 3 thresholds will increase twofold when C1 queue size " \ "reaches this amount per compiler thread") \ range(0, max_jint) \ \ product(intx, Tier4LoadFeedback, 3, \ "Tier 4 thresholds will increase twofold when C2 queue size " \ "reaches this amount per compiler thread") \ range(0, max_jint) \ \ product(intx, TieredCompileTaskTimeout, 50, \ "Kill compile task if method was not used within " \ "given timeout in milliseconds") \ range(0, max_intx) \ \ product(intx, TieredStopAtLevel, 4, \ "Stop at given compilation level") \ range(0, 4) \ \ product(intx, Tier0ProfilingStartPercentage, 200, \ "Start profiling in interpreter if the counters exceed tier 3 " \ "thresholds (tier 4 thresholds with " \ "CompilationMode=high-only|high-only-quick-internal)" \ "by the specified percentage") \ range(0, max_jint) \ \ product(uintx, IncreaseFirstTierCompileThresholdAt, 50, \ "Increase the compile threshold for C1 compilation if the code " \ "cache is filled by the specified percentage") \ range(0, 99) \ \ product(intx, TieredRateUpdateMinTime, 1, \ "Minimum rate sampling interval (in milliseconds)") \ range(0, max_intx) \ \ product(intx, TieredRateUpdateMaxTime, 25, \ "Maximum rate sampling interval (in milliseconds)") \ range(0, max_intx) \ \ product(ccstr, CompilationMode, "default", \ "Compilation modes: " \ "default: normal tiered compilation; " \ "quick-only: C1-only mode; " \ "high-only: C2/JVMCI-only mode; " \ "high-only-quick-internal: C2/JVMCI-only mode, " \ "with JVMCI compiler compiled with C1.") \ \ product_pd(bool, TieredCompilation, \ "Enable tiered compilation") \ \ product(bool, PrintTieredEvents, false, \ "Print tiered events notifications") \ \ product_pd(intx, OnStackReplacePercentage, \ "NON_TIERED number of method invocations/branches (expressed as " \ "% of CompileThreshold) before (re-)compiling OSR code") \ constraint(OnStackReplacePercentageConstraintFunc, AfterErgo) \ \ product(intx, InterpreterProfilePercentage, 33, \ "NON_TIERED number of method invocations/branches (expressed as " \ "% of CompileThreshold) before profiling in the interpreter") \ range(0, 100) \ \ develop(intx, DesiredMethodLimit, 8000, \ "The desired maximum method size (in bytecodes) after inlining") \ \ develop(intx, HugeMethodLimit, 8000, \ "Don't compile methods larger than this if " \ "+DontCompileHugeMethods") \ \ /* Properties for Java libraries */ \ \ product(uint64_t, MaxDirectMemorySize, 0, \ "Maximum total size of NIO direct-buffer allocations") \ range(0, max_jlong) \ \ /* Flags used for temporary code during development */ \ \ diagnostic(bool, UseNewCode, false, \ "Testing Only: Use the new version while testing") \ \ diagnostic(bool, UseNewCode2, false, \ "Testing Only: Use the new version while testing") \ \ diagnostic(bool, UseNewCode3, false, \ "Testing Only: Use the new version while testing") \ \ /* flags for performance data collection */ \ \ product(bool, UsePerfData, true, \ "Flag to disable jvmstat instrumentation for performance testing "\ "and problem isolation purposes") \ \ product(bool, PerfDataSaveToFile, false, \ "Save PerfData memory to hsperfdata_ file on exit") \ \ product(ccstr, PerfDataSaveFile, NULL, \ "Save PerfData memory to the specified absolute pathname. " \ "The string %p in the file name (if present) " \ "will be replaced by pid") \ \ product(intx, PerfDataSamplingInterval, 50, \ "Data sampling interval (in milliseconds)") \ range(PeriodicTask::min_interval, max_jint) \ constraint(PerfDataSamplingIntervalFunc, AfterErgo) \ \ product(bool, PerfDisableSharedMem, false, \ "Store performance data in standard memory") \ \ product(intx, PerfDataMemorySize, 32*K, \ "Size of performance data memory region. Will be rounded " \ "up to a multiple of the native os page size.") \ range(128, 32*64*K) \ \ product(intx, PerfMaxStringConstLength, 1024, \ "Maximum PerfStringConstant string length before truncation") \ range(32, 32*K) \ \ product(bool, PerfAllowAtExitRegistration, false, \ "Allow registration of atexit() methods") \ \ product(bool, PerfBypassFileSystemCheck, false, \ "Bypass Win32 file system criteria checks (Windows Only)") \ \ product(intx, UnguardOnExecutionViolation, 0, \ "Unguard page and retry on no-execute fault (Win32 only) " \ "0=off, 1=conservative, 2=aggressive") \ range(0, 2) \ \ /* Serviceability Support */ \ \ product(bool, ManagementServer, false, \ "Create JMX Management Server") \ \ product(bool, DisableAttachMechanism, false, \ "Disable mechanism that allows tools to attach to this VM") \ \ product(bool, StartAttachListener, false, \ "Always start Attach Listener at VM startup") \ \ product(bool, EnableDynamicAgentLoading, true, \ "Allow tools to load agents with the attach mechanism") \ \ manageable(bool, PrintConcurrentLocks, false, \ "Print java.util.concurrent locks in thread dump") \ \ /* Shared spaces */ \ \ product(bool, UseSharedSpaces, true, \ "Use shared spaces for metadata") \ \ product(bool, VerifySharedSpaces, false, \ "Verify integrity of shared spaces") \ \ product(bool, RequireSharedSpaces, false, \ "Require shared spaces for metadata") \ \ product(bool, DumpSharedSpaces, false, \ "Special mode: JVM reads a class list, loads classes, builds " \ "shared spaces, and dumps the shared spaces to a file to be " \ "used in future JVM runs") \ \ product(bool, DynamicDumpSharedSpaces, false, \ "Dynamic archive") \ \ product(bool, PrintSharedArchiveAndExit, false, \ "Print shared archive file contents") \ \ product(bool, PrintSharedDictionary, false, \ "If PrintSharedArchiveAndExit is true, also print the shared " \ "dictionary") \ \ product(size_t, SharedBaseAddress, LP64_ONLY(32*G) \ NOT_LP64(LINUX_ONLY(2*G) NOT_LINUX(0)), \ "Address to allocate shared memory region for class data") \ range(0, SIZE_MAX) \ \ product(ccstr, SharedArchiveConfigFile, NULL, \ "Data to add to the CDS archive file") \ \ product(uintx, SharedSymbolTableBucketSize, 4, \ "Average number of symbols per bucket in shared table") \ range(2, 246) \ \ diagnostic(bool, AllowArchivingWithJavaAgent, false, \ "Allow Java agent to be run with CDS dumping") \ \ diagnostic(bool, PrintMethodHandleStubs, false, \ "Print generated stub code for method handles") \ \ diagnostic(bool, VerifyMethodHandles, trueInDebug, \ "perform extra checks when constructing method handles") \ \ diagnostic(bool, ShowHiddenFrames, false, \ "show method handle implementation frames (usually hidden)") \ \ experimental(bool, TrustFinalNonStaticFields, false, \ "trust final non-static declarations for constant folding") \ \ diagnostic(bool, FoldStableValues, true, \ "Optimize loads from stable fields (marked w/ @Stable)") \ \ diagnostic(int, UseBootstrapCallInfo, 1, \ "0: when resolving InDy or ConDy, force all BSM arguments to be " \ "resolved before the bootstrap method is called; 1: when a BSM " \ "that may accept a BootstrapCallInfo is detected, use that API " \ "to pass BSM arguments, which allows the BSM to delay their " \ "resolution; 2+: stress test the BCI API by calling more BSMs " \ "via that API, instead of with the eagerly-resolved array.") \ \ diagnostic(bool, PauseAtStartup, false, \ "Causes the VM to pause at startup time and wait for the pause " \ "file to be removed (default: ./vm.paused.)") \ \ diagnostic(ccstr, PauseAtStartupFile, NULL, \ "The file to create and for whose removal to await when pausing " \ "at startup. (default: ./vm.paused.)") \ \ diagnostic(bool, PauseAtExit, false, \ "Pause and wait for keypress on exit if a debugger is attached") \ \ product(bool, ExtendedDTraceProbes, false, \ "Enable performance-impacting dtrace probes") \ \ product(bool, DTraceMethodProbes, false, \ "Enable dtrace probes for method-entry and method-exit") \ \ product(bool, DTraceAllocProbes, false, \ "Enable dtrace probes for object allocation") \ \ product(bool, DTraceMonitorProbes, false, \ "Enable dtrace probes for monitor events") \ \ product(bool, RelaxAccessControlCheck, false, \ "Relax the access control checks in the verifier") \ \ product(uintx, StringTableSize, defaultStringTableSize, \ "Number of buckets in the interned String table " \ "(will be rounded to nearest higher power of 2)") \ range(minimumStringTableSize, 16777216ul /* 2^24 */) \ \ experimental(uintx, SymbolTableSize, defaultSymbolTableSize, \ "Number of buckets in the JVM internal Symbol table") \ range(minimumSymbolTableSize, 16777216ul /* 2^24 */) \ \ product(bool, UseStringDeduplication, false, \ "Use string deduplication") \ \ product(uintx, StringDeduplicationAgeThreshold, 3, \ "A string must reach this age (or be promoted to an old region) " \ "to be considered for deduplication") \ range(1, markWord::max_age) \ \ diagnostic(bool, StringDeduplicationResizeALot, false, \ "Force table resize every time the table is scanned") \ \ diagnostic(bool, StringDeduplicationRehashALot, false, \ "Force table rehash every time the table is scanned") \ \ diagnostic(bool, WhiteBoxAPI, false, \ "Enable internal testing APIs") \ \ experimental(intx, SurvivorAlignmentInBytes, 0, \ "Default survivor space alignment in bytes") \ range(8, 256) \ constraint(SurvivorAlignmentInBytesConstraintFunc,AfterErgo) \ \ product(ccstr, DumpLoadedClassList, NULL, \ "Dump the names all loaded classes, that could be stored into " \ "the CDS archive, in the specified file") \ \ product(ccstr, SharedClassListFile, NULL, \ "Override the default CDS class list") \ \ product(ccstr, SharedArchiveFile, NULL, \ "Override the default location of the CDS archive file") \ \ product(ccstr, ArchiveClassesAtExit, NULL, \ "The path and name of the dynamic archive file") \ \ product(ccstr, ExtraSharedClassListFile, NULL, \ "Extra classlist for building the CDS archive file") \ \ diagnostic(intx, ArchiveRelocationMode, 0, \ "(0) first map at preferred address, and if " \ "unsuccessful, map at alternative address (default); " \ "(1) always map at alternative address; " \ "(2) always map at preferred address, and if unsuccessful, " \ "do not map the archive") \ range(0, 2) \ \ experimental(size_t, ArrayAllocatorMallocLimit, (size_t)-1, \ "Allocation less than this value will be allocated " \ "using malloc. Larger allocations will use mmap.") \ \ experimental(bool, AlwaysAtomicAccesses, false, \ "Accesses to all variables should always be atomic") \ \ diagnostic(bool, UseUnalignedAccesses, false, \ "Use unaligned memory accesses in Unsafe") \ \ product_pd(bool, PreserveFramePointer, \ "Use the FP register for holding the frame pointer " \ "and not as a general purpose register.") \ \ diagnostic(bool, CheckIntrinsics, true, \ "When a class C is loaded, check that " \ "(1) all intrinsics defined by the VM for class C are present "\ "in the loaded class file and are marked with the " \ "@HotSpotIntrinsicCandidate annotation, that " \ "(2) there is an intrinsic registered for all loaded methods " \ "that are annotated with the @HotSpotIntrinsicCandidate " \ "annotation, and that " \ "(3) no orphan methods exist for class C (i.e., methods for " \ "which the VM declares an intrinsic but that are not declared "\ "in the loaded class C. " \ "Check (3) is available only in debug builds.") \ \ diagnostic_pd(intx, InitArrayShortSize, \ "Threshold small size (in bytes) for clearing arrays. " \ "Anything this size or smaller may get converted to discrete " \ "scalar stores.") \ range(0, max_intx) \ constraint(InitArrayShortSizeConstraintFunc, AfterErgo) \ \ diagnostic(bool, CompilerDirectivesIgnoreCompileCommands, false, \ "Disable backwards compatibility for compile commands.") \ \ diagnostic(bool, CompilerDirectivesPrint, false, \ "Print compiler directives on installation.") \ diagnostic(int, CompilerDirectivesLimit, 50, \ "Limit on number of compiler directives.") \ \ product(ccstr, AllocateHeapAt, NULL, \ "Path to the directoy where a temporary file will be created " \ "to use as the backing store for Java Heap.") \ \ experimental(ccstr, AllocateOldGenAt, NULL, \ "Path to the directoy where a temporary file will be " \ "created to use as the backing store for old generation." \ "File of size Xmx is pre-allocated for performance reason, so" \ "we need that much space available") \ \ develop(int, VerifyMetaspaceInterval, DEBUG_ONLY(500) NOT_DEBUG(0), \ "Run periodic metaspace verifications (0 - none, " \ "1 - always, >1 every nth interval)") \ \ diagnostic(bool, ShowRegistersOnAssert, true, \ "On internal errors, include registers in error report.") \ \ diagnostic(bool, UseSwitchProfiling, true, \ "leverage profiling for table/lookup switch") \ \ develop(bool, TraceMemoryWriteback, false, \ "Trace memory writeback operations") \ \ JFR_ONLY(product(bool, FlightRecorder, false, \ "(Deprecated) Enable Flight Recorder")) \ \ JFR_ONLY(product(ccstr, FlightRecorderOptions, NULL, \ "Flight Recorder options")) \ \ JFR_ONLY(product(ccstr, StartFlightRecording, NULL, \ "Start flight recording with options")) \ \ experimental(bool, UseFastUnorderedTimeStamps, false, \ "Use platform unstable time where supported for timestamps only") \ \ product(bool, UseNewFieldLayout, true, \ "(Deprecated) Use new algorithm to compute field layouts") \ \ product(bool, UseEmptySlotsInSupers, true, \ "Allow allocating fields in empty slots of super-classes") \ \ diagnostic(bool, DeoptimizeNMethodBarriersALot, false, \ "Make nmethod barriers deoptimise a lot.") \ // Interface macros #define DECLARE_PRODUCT_FLAG(type, name, value, doc) extern "C" type name; #define DECLARE_PD_PRODUCT_FLAG(type, name, doc) extern "C" type name; #define DECLARE_DIAGNOSTIC_FLAG(type, name, value, doc) extern "C" type name; #define DECLARE_PD_DIAGNOSTIC_FLAG(type, name, doc) extern "C" type name; #define DECLARE_EXPERIMENTAL_FLAG(type, name, value, doc) extern "C" type name; #define DECLARE_MANAGEABLE_FLAG(type, name, value, doc) extern "C" type name; #define DECLARE_PRODUCT_RW_FLAG(type, name, value, doc) extern "C" type name; #ifdef PRODUCT #define DECLARE_DEVELOPER_FLAG(type, name, value, doc) const type name = value; #define DECLARE_PD_DEVELOPER_FLAG(type, name, doc) const type name = pd_##name; #define DECLARE_NOTPRODUCT_FLAG(type, name, value, doc) const type name = value; #else #define DECLARE_DEVELOPER_FLAG(type, name, value, doc) extern "C" type name; #define DECLARE_PD_DEVELOPER_FLAG(type, name, doc) extern "C" type name; #define DECLARE_NOTPRODUCT_FLAG(type, name, value, doc) extern "C" type name; #endif // PRODUCT // Special LP64 flags, product only needed for now. #ifdef _LP64 #define DECLARE_LP64_PRODUCT_FLAG(type, name, value, doc) extern "C" type name; #else #define DECLARE_LP64_PRODUCT_FLAG(type, name, value, doc) const type name = value; #endif // _LP64 ALL_FLAGS(DECLARE_DEVELOPER_FLAG, \ DECLARE_PD_DEVELOPER_FLAG, \ DECLARE_PRODUCT_FLAG, \ DECLARE_PD_PRODUCT_FLAG, \ DECLARE_DIAGNOSTIC_FLAG, \ DECLARE_PD_DIAGNOSTIC_FLAG, \ DECLARE_EXPERIMENTAL_FLAG, \ DECLARE_NOTPRODUCT_FLAG, \ DECLARE_MANAGEABLE_FLAG, \ DECLARE_PRODUCT_RW_FLAG, \ DECLARE_LP64_PRODUCT_FLAG, \ IGNORE_RANGE, \ IGNORE_CONSTRAINT) #endif // SHARE_RUNTIME_GLOBALS_HPP