1 /* 2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2017, Red Hat, Inc. and/or its affiliates. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26 #include "precompiled.hpp" 27 #include "gc/parallel/parallelArguments.hpp" 28 #include "gc/parallel/parallelScavengeHeap.hpp" 29 #include "gc/shared/adaptiveSizePolicy.hpp" 30 #include "gc/shared/collectorPolicy.hpp" 31 #include "gc/shared/gcArguments.inline.hpp" 32 #include "runtime/globals.hpp" 33 #include "runtime/globals_extension.hpp" 34 #include "runtime/java.hpp" 35 #include "runtime/vm_version.hpp" 36 #include "utilities/defaultStream.hpp" 37 38 size_t ParallelArguments::conservative_max_heap_alignment() { 39 return CollectorPolicy::compute_heap_alignment(); 40 } 41 42 void ParallelArguments::initialize() { 43 GCArguments::initialize(); 44 assert(UseParallelGC || UseParallelOldGC, "Error"); 45 // Enable ParallelOld unless it was explicitly disabled (cmd line or rc file). 46 if (FLAG_IS_DEFAULT(UseParallelOldGC)) { 47 FLAG_SET_DEFAULT(UseParallelOldGC, true); 48 } 49 FLAG_SET_DEFAULT(UseParallelGC, true); 50 51 // If no heap maximum was requested explicitly, use some reasonable fraction 52 // of the physical memory, up to a maximum of 1GB. 53 FLAG_SET_DEFAULT(ParallelGCThreads, 54 VM_Version::parallel_worker_threads()); 55 if (ParallelGCThreads == 0) { 56 jio_fprintf(defaultStream::error_stream(), 57 "The Parallel GC can not be combined with -XX:ParallelGCThreads=0\n"); 58 vm_exit(1); 59 } 60 61 if (UseAdaptiveSizePolicy) { 62 // We don't want to limit adaptive heap sizing's freedom to adjust the heap 63 // unless the user actually sets these flags. 64 if (FLAG_IS_DEFAULT(MinHeapFreeRatio)) { 65 FLAG_SET_DEFAULT(MinHeapFreeRatio, 0); 66 } 67 if (FLAG_IS_DEFAULT(MaxHeapFreeRatio)) { 68 FLAG_SET_DEFAULT(MaxHeapFreeRatio, 100); 69 } 70 } 71 72 // If InitialSurvivorRatio or MinSurvivorRatio were not specified, but the 73 // SurvivorRatio has been set, reset their default values to SurvivorRatio + 74 // 2. By doing this we make SurvivorRatio also work for Parallel Scavenger. 75 // See CR 6362902 for details. 76 if (!FLAG_IS_DEFAULT(SurvivorRatio)) { 77 if (FLAG_IS_DEFAULT(InitialSurvivorRatio)) { 78 FLAG_SET_DEFAULT(InitialSurvivorRatio, SurvivorRatio + 2); 79 } 80 if (FLAG_IS_DEFAULT(MinSurvivorRatio)) { 81 FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2); 82 } 83 } 84 85 if (UseParallelOldGC) { 86 // Par compact uses lower default values since they are treated as 87 // minimums. These are different defaults because of the different 88 // interpretation and are not ergonomically set. 89 if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) { 90 FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1); 91 } 92 } 93 } 94 95 CollectedHeap* ParallelArguments::create_heap() { 96 return create_heap_with_policy<ParallelScavengeHeap, GenerationSizer>(); 97 }