--- /dev/null 2017-03-07 11:44:12.271151064 +0100 +++ new/src/hotspot/share/gc/parallel/parallelArguments.cpp 2017-10-25 16:45:19.520405379 +0200 @@ -0,0 +1,89 @@ +/* + * Copyright (c) 2017, Red Hat, Inc. and/or its affiliates. + * 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. + * + */ + +#include "precompiled.hpp" +#include "gc/parallel/parallelArguments.hpp" +#include "gc/shared/collectorPolicy.hpp" +#include "runtime/globals.hpp" +#include "runtime/globals_extension.hpp" +#include "runtime/java.hpp" +#include "runtime/vm_version.hpp" +#include "utilities/defaultStream.hpp" + +size_t ParallelArguments::conservative_max_heap_alignment() { + return CollectorPolicy::compute_heap_alignment(); +} + +void ParallelArguments::initialize_flags() { + GCArguments::initialize_flags(); + assert(UseParallelGC || UseParallelOldGC, "Error"); + // Enable ParallelOld unless it was explicitly disabled (cmd line or rc file). + if (FLAG_IS_DEFAULT(UseParallelOldGC)) { + FLAG_SET_DEFAULT(UseParallelOldGC, true); + } + FLAG_SET_DEFAULT(UseParallelGC, true); + + // If no heap maximum was requested explicitly, use some reasonable fraction + // of the physical memory, up to a maximum of 1GB. + FLAG_SET_DEFAULT(ParallelGCThreads, + Abstract_VM_Version::parallel_worker_threads()); + if (ParallelGCThreads == 0) { + jio_fprintf(defaultStream::error_stream(), + "The Parallel GC can not be combined with -XX:ParallelGCThreads=0\n"); + vm_exit(1); + } + + if (UseAdaptiveSizePolicy) { + // We don't want to limit adaptive heap sizing's freedom to adjust the heap + // unless the user actually sets these flags. + if (FLAG_IS_DEFAULT(MinHeapFreeRatio)) { + FLAG_SET_DEFAULT(MinHeapFreeRatio, 0); + } + if (FLAG_IS_DEFAULT(MaxHeapFreeRatio)) { + FLAG_SET_DEFAULT(MaxHeapFreeRatio, 100); + } + } + + // If InitialSurvivorRatio or MinSurvivorRatio were not specified, but the + // SurvivorRatio has been set, reset their default values to SurvivorRatio + + // 2. By doing this we make SurvivorRatio also work for Parallel Scavenger. + // See CR 6362902 for details. + if (!FLAG_IS_DEFAULT(SurvivorRatio)) { + if (FLAG_IS_DEFAULT(InitialSurvivorRatio)) { + FLAG_SET_DEFAULT(InitialSurvivorRatio, SurvivorRatio + 2); + } + if (FLAG_IS_DEFAULT(MinSurvivorRatio)) { + FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2); + } + } + + if (UseParallelOldGC) { + // Par compact uses lower default values since they are treated as + // minimums. These are different defaults because of the different + // interpretation and are not ergonomically set. + if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) { + FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1); + } + } +}