src/share/vm/gc_implementation/g1/evacuationInfo.hpp

Fri, 10 Oct 2014 15:51:58 +0200

author
tschatzl
date
Fri, 10 Oct 2014 15:51:58 +0200
changeset 7257
e7d0505c8a30
parent 0
f90c822e73f8
permissions
-rw-r--r--

8059758: Footprint regressions with JDK-8038423
Summary: Changes in JDK-8038423 always initialize (zero out) virtual memory used for auxiliary data structures. This causes a footprint regression for G1 in startup benchmarks. This is because they do not touch that memory at all, so the operating system does not actually commit these pages. The fix is to, if the initialization value of the data structures matches the default value of just committed memory (=0), do not do anything.
Reviewed-by: jwilhelm, brutisso

aoqi@0 1 /*
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aoqi@0 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0 4 *
aoqi@0 5 * This code is free software; you can redistribute it and/or modify it
aoqi@0 6 * under the terms of the GNU General Public License version 2 only, as
aoqi@0 7 * published by the Free Software Foundation.
aoqi@0 8 *
aoqi@0 9 * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
aoqi@0 12 * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0 13 * accompanied this code).
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aoqi@0 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0 20 * or visit www.oracle.com if you need additional information or have any
aoqi@0 21 * questions.
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aoqi@0 23 */
aoqi@0 24
aoqi@0 25 #ifndef SHARE_VM_GC_IMPLEMENTATION_SHARED_EVACUATIONINFO_HPP
aoqi@0 26 #define SHARE_VM_GC_IMPLEMENTATION_SHARED_EVACUATIONINFO_HPP
aoqi@0 27
aoqi@0 28 #include "memory/allocation.hpp"
aoqi@0 29
aoqi@0 30 class EvacuationInfo : public StackObj {
aoqi@0 31 uint _collectionset_regions;
aoqi@0 32 uint _allocation_regions;
aoqi@0 33 size_t _collectionset_used_before;
aoqi@0 34 size_t _collectionset_used_after;
aoqi@0 35 size_t _alloc_regions_used_before;
aoqi@0 36 size_t _bytes_copied;
aoqi@0 37 uint _regions_freed;
aoqi@0 38
aoqi@0 39 public:
aoqi@0 40 EvacuationInfo() : _collectionset_regions(0), _allocation_regions(0), _collectionset_used_before(0),
aoqi@0 41 _collectionset_used_after(0), _alloc_regions_used_before(0),
aoqi@0 42 _bytes_copied(0), _regions_freed(0) { }
aoqi@0 43
aoqi@0 44 void set_collectionset_regions(uint collectionset_regions) {
aoqi@0 45 _collectionset_regions = collectionset_regions;
aoqi@0 46 }
aoqi@0 47
aoqi@0 48 void set_allocation_regions(uint allocation_regions) {
aoqi@0 49 _allocation_regions = allocation_regions;
aoqi@0 50 }
aoqi@0 51
aoqi@0 52 void set_collectionset_used_before(size_t used) {
aoqi@0 53 _collectionset_used_before = used;
aoqi@0 54 }
aoqi@0 55
aoqi@0 56 void increment_collectionset_used_after(size_t used) {
aoqi@0 57 _collectionset_used_after += used;
aoqi@0 58 }
aoqi@0 59
aoqi@0 60 void set_alloc_regions_used_before(size_t used) {
aoqi@0 61 _alloc_regions_used_before = used;
aoqi@0 62 }
aoqi@0 63
aoqi@0 64 void set_bytes_copied(size_t copied) {
aoqi@0 65 _bytes_copied = copied;
aoqi@0 66 }
aoqi@0 67
aoqi@0 68 void set_regions_freed(uint freed) {
aoqi@0 69 _regions_freed += freed;
aoqi@0 70 }
aoqi@0 71
aoqi@0 72 uint collectionset_regions() { return _collectionset_regions; }
aoqi@0 73 uint allocation_regions() { return _allocation_regions; }
aoqi@0 74 size_t collectionset_used_before() { return _collectionset_used_before; }
aoqi@0 75 size_t collectionset_used_after() { return _collectionset_used_after; }
aoqi@0 76 size_t alloc_regions_used_before() { return _alloc_regions_used_before; }
aoqi@0 77 size_t bytes_copied() { return _bytes_copied; }
aoqi@0 78 uint regions_freed() { return _regions_freed; }
aoqi@0 79 };
aoqi@0 80
aoqi@0 81 #endif // SHARE_VM_GC_IMPLEMENTATION_SHARED_EVACUATIONINFO_HPP

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