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src/hotspot/os/aix/globals_aix.hpp
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*** 25,90 ****
#ifndef OS_AIX_GLOBALS_AIX_HPP
#define OS_AIX_GLOBALS_AIX_HPP
//
! // Defines Aix specific flags. They are not available on other platforms.
//
// (Please keep the switches sorted alphabetically.)
! #define RUNTIME_OS_FLAGS(develop, \
! develop_pd, \
! product, \
! product_pd, \
! diagnostic, \
! diagnostic_pd, \
! notproduct, \
! range, \
! constraint) \
! \
! /* Whether to allow the VM to run if EXTSHM=ON. EXTSHM is an environment */ \
! /* variable used on AIX to activate certain hacks which allow more shm segments */\
! /* for 32bit processes. For 64bit processes, it is pointless and may have */ \
! /* harmful side effects (e.g. for some reasonn prevents allocation of 64k pages */\
! /* via shmctl). */ \
! /* Per default we quit with an error if that variable is found; for certain */ \
! /* customer scenarios, we may want to be able to run despite that variable. */ \
! product(bool, AllowExtshm, false, \
! "Allow VM to run with EXTSHM=ON.") \
! \
! /* Maximum expected size of the data segment. That correlates with the */ \
! /* to the maximum C Heap consumption we expect. */ \
! /* We need to know this because we need to leave "breathing space" for the */ \
! /* data segment when placing the java heap. If that space is too small, we */ \
! /* reduce our chance of getting a low heap address (needed for compressed */ \
! /* Oops). */ \
! product(uintx, MaxExpectedDataSegmentSize, 8*G, \
! "Maximum expected Data Segment Size.") \
! \
! /* Use optimized addresses for the polling page. */ \
! product(bool, OptimizePollingPageLocation, true, \
! "Optimize the location of the polling page used for Safepoints") \
! \
! /* Use 64K pages for virtual memory (shmat). */ \
! product(bool, Use64KPages, true, \
! "Use 64K pages if available.") \
! \
! /* If VM uses 64K paged memory (shmat) for virtual memory: threshold below */ \
! /* which virtual memory allocations are done with 4K memory (mmap). This is */ \
! /* mainly for test purposes. */ \
! develop(uintx, Use64KPagesThreshold, 0, \
! "4K/64K page allocation threshold.") \
! \
! /* Normally AIX commits memory on touch, but sometimes it is helpful to have */ \
! /* explicit commit behaviour. This flag, if true, causes the VM to touch */ \
! /* memory on os::commit_memory() (which normally is a noop). */ \
! product(bool, UseExplicitCommit, false, \
! "Explicit commit for virtual memory.") \
! \
//
! // Defines Aix-specific default values. The flags are available on all
// platforms, but they may have different default values on other platforms.
//
// UseLargePages means nothing, for now, on AIX.
// Use Use64KPages or Use16MPages instead.
--- 25,85 ----
#ifndef OS_AIX_GLOBALS_AIX_HPP
#define OS_AIX_GLOBALS_AIX_HPP
//
! // Declare Aix specific flags. They are not available on other platforms.
//
// (Please keep the switches sorted alphabetically.)
! #include "runtime/flags/jvmFlag.hpp"
+ // Whether to allow the VM to run if EXTSHM=ON. EXTSHM is an environment
+ // variable used on AIX to activate certain hacks which allow more shm segments
+ // for 32bit processes. For 64bit processes, it is pointless and may have
+ // harmful side effects (e.g. for some reasonn prevents allocation of 64k pages
+ // via shmctl).
+ // Per default we quit with an error if that variable is found; for certain
+ // customer scenarios, we may want to be able to run despite that variable.
+ PRODUCT_FLAG(bool, AllowExtshm, false, JVMFlag::DEFAULT,
+ "Allow VM to run with EXTSHM=ON.");
+
+
+ // Maximum expected size of the data segment. That correlates with the
+ // to the maximum C Heap consumption we expect.
+ // We need to know this because we need to leave "breathing space" for the
+ // data segment when placing the java heap. If that space is too small, we
+ // reduce our chance of getting a low heap address (needed for compressed
+ // Oops).
+ PRODUCT_FLAG(uintx, MaxExpectedDataSegmentSize, 8*G, JVMFlag::DEFAULT,
+ "Maximum expected Data Segment Size.");
+
+
+ // Use optimized addresses for the polling page.
+ PRODUCT_FLAG(bool, OptimizePollingPageLocation, true, JVMFlag::DEFAULT,
+ "Optimize the location of the polling page used for Safepoints");
+
+
+ // Use 64K pages for virtual memory (shmat).
+ PRODUCT_FLAG(bool, Use64KPages, true, JVMFlag::DEFAULT,
+ "Use 64K pages if available.");
+
+
+ // If VM uses 64K paged memory (shmat) for virtual memory: threshold below
+ // which virtual memory allocations are done with 4K memory (mmap). This is
+ // mainly for test purposes.
+ DEVELOP_FLAG(uintx, Use64KPagesThreshold, 0, JVMFlag::DEFAULT,
+ "4K/64K page allocation threshold.");
+
+
+ // Normally AIX commits memory on touch, but sometimes it is helpful to have
+ // explicit commit behaviour. This flag, if true, causes the VM to touch
+ // memory on os::commit_memory() (which normally is a noop).
+ PRODUCT_FLAG(bool, UseExplicitCommit, false, JVMFlag::DEFAULT,
+ "Explicit commit for virtual memory.");
//
! // Define Aix-specific default values. The flags are available on all
// platforms, but they may have different default values on other platforms.
//
// UseLargePages means nothing, for now, on AIX.
// Use Use64KPages or Use16MPages instead.
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