1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/gc_implementation/parallelScavenge/asPSOldGen.cpp Wed Apr 27 01:25:04 2016 +0800
1.3 @@ -0,0 +1,149 @@
1.4 +/*
1.5 + * Copyright (c) 2003, 2014, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#include "precompiled.hpp"
1.29 +#include "gc_implementation/parallelScavenge/asPSOldGen.hpp"
1.30 +#include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
1.31 +#include "gc_implementation/parallelScavenge/psAdaptiveSizePolicy.hpp"
1.32 +#include "gc_implementation/parallelScavenge/psMarkSweepDecorator.hpp"
1.33 +#include "memory/cardTableModRefBS.hpp"
1.34 +#include "oops/oop.inline.hpp"
1.35 +#include "runtime/java.hpp"
1.36 +
1.37 +// Whereas PSOldGen takes the maximum size of the generation
1.38 +// (which doesn't change in the case of PSOldGen) as a parameter,
1.39 +// ASPSOldGen takes the upper limit on the size of
1.40 +// the generation as a parameter. In ASPSOldGen the
1.41 +// maximum size of the generation can change as the boundary
1.42 +// moves. The "maximum size of the generation" is still a valid
1.43 +// concept since the generation can grow and shrink within that
1.44 +// maximum. There are lots of useful checks that use that
1.45 +// maximum. In PSOldGen the method max_gen_size() returns
1.46 +// _max_gen_size (as set by the PSOldGen constructor). This
1.47 +// is how it always worked. In ASPSOldGen max_gen_size()
1.48 +// returned the size of the reserved space for the generation.
1.49 +// That can change as the boundary moves. Below the limit of
1.50 +// the size of the generation is passed to the PSOldGen constructor
1.51 +// for "_max_gen_size" (have to pass something) but it is not used later.
1.52 +//
1.53 +ASPSOldGen::ASPSOldGen(size_t initial_size,
1.54 + size_t min_size,
1.55 + size_t size_limit,
1.56 + const char* gen_name,
1.57 + int level) :
1.58 + PSOldGen(initial_size, min_size, size_limit, gen_name, level),
1.59 + _gen_size_limit(size_limit)
1.60 +{}
1.61 +
1.62 +ASPSOldGen::ASPSOldGen(PSVirtualSpace* vs,
1.63 + size_t initial_size,
1.64 + size_t min_size,
1.65 + size_t size_limit,
1.66 + const char* gen_name,
1.67 + int level) :
1.68 + PSOldGen(initial_size, min_size, size_limit, gen_name, level),
1.69 + _gen_size_limit(size_limit)
1.70 +{
1.71 + _virtual_space = vs;
1.72 +}
1.73 +
1.74 +void ASPSOldGen::initialize_work(const char* perf_data_name, int level) {
1.75 + PSOldGen::initialize_work(perf_data_name, level);
1.76 +
1.77 + // The old gen can grow to gen_size_limit(). _reserve reflects only
1.78 + // the current maximum that can be committed.
1.79 + assert(_reserved.byte_size() <= gen_size_limit(), "Consistency check");
1.80 +
1.81 + initialize_performance_counters(perf_data_name, level);
1.82 +}
1.83 +
1.84 +void ASPSOldGen::reset_after_change() {
1.85 + _reserved = MemRegion((HeapWord*)virtual_space()->low_boundary(),
1.86 + (HeapWord*)virtual_space()->high_boundary());
1.87 + post_resize();
1.88 +}
1.89 +
1.90 +
1.91 +size_t ASPSOldGen::available_for_expansion() {
1.92 + assert(virtual_space()->is_aligned(gen_size_limit()), "not aligned");
1.93 + assert(gen_size_limit() >= virtual_space()->committed_size(), "bad gen size");
1.94 +
1.95 + ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
1.96 + size_t result = gen_size_limit() - virtual_space()->committed_size();
1.97 + size_t result_aligned = align_size_down(result, heap->generation_alignment());
1.98 + return result_aligned;
1.99 +}
1.100 +
1.101 +size_t ASPSOldGen::available_for_contraction() {
1.102 + size_t uncommitted_bytes = virtual_space()->uncommitted_size();
1.103 + if (uncommitted_bytes != 0) {
1.104 + return uncommitted_bytes;
1.105 + }
1.106 +
1.107 + ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
1.108 + const size_t gen_alignment = heap->generation_alignment();
1.109 + PSAdaptiveSizePolicy* policy = heap->size_policy();
1.110 + const size_t working_size =
1.111 + used_in_bytes() + (size_t) policy->avg_promoted()->padded_average();
1.112 + const size_t working_aligned = align_size_up(working_size, gen_alignment);
1.113 + const size_t working_or_min = MAX2(working_aligned, min_gen_size());
1.114 + if (working_or_min > reserved().byte_size()) {
1.115 + // If the used or minimum gen size (aligned up) is greater
1.116 + // than the total reserved size, then the space available
1.117 + // for contraction should (after proper alignment) be 0
1.118 + return 0;
1.119 + }
1.120 + const size_t max_contraction =
1.121 + reserved().byte_size() - working_or_min;
1.122 +
1.123 + // Use the "increment" fraction instead of the "decrement" fraction
1.124 + // to allow the other gen to expand more aggressively. The
1.125 + // "decrement" fraction is conservative because its intent is to
1.126 + // only reduce the footprint.
1.127 +
1.128 + size_t result = policy->promo_increment_aligned_down(max_contraction);
1.129 + // Also adjust for inter-generational alignment
1.130 + size_t result_aligned = align_size_down(result, gen_alignment);
1.131 + if (PrintAdaptiveSizePolicy && Verbose) {
1.132 + gclog_or_tty->print_cr("\nASPSOldGen::available_for_contraction:"
1.133 + " " SSIZE_FORMAT " K / " SIZE_FORMAT_HEX, (result_aligned/K), result_aligned);
1.134 + gclog_or_tty->print_cr(" reserved().byte_size() " SSIZE_FORMAT " K / " SIZE_FORMAT_HEX " ",
1.135 + (reserved().byte_size()/K), reserved().byte_size());
1.136 + size_t working_promoted = (size_t) policy->avg_promoted()->padded_average();
1.137 + gclog_or_tty->print_cr(" padded promoted " SSIZE_FORMAT " K / " SIZE_FORMAT_HEX,
1.138 + (working_promoted/K), working_promoted);
1.139 + gclog_or_tty->print_cr(" used " SSIZE_FORMAT " K / " SIZE_FORMAT_HEX,
1.140 + (used_in_bytes()/K), used_in_bytes());
1.141 + gclog_or_tty->print_cr(" min_gen_size() " SSIZE_FORMAT " K / " SIZE_FORMAT_HEX,
1.142 + (min_gen_size()/K), min_gen_size());
1.143 + gclog_or_tty->print_cr(" max_contraction " SSIZE_FORMAT " K / " SIZE_FORMAT_HEX,
1.144 + (max_contraction/K), max_contraction);
1.145 + gclog_or_tty->print_cr(" without alignment " SSIZE_FORMAT " K / " SIZE_FORMAT_HEX,
1.146 + (policy->promo_increment(max_contraction)/K),
1.147 + policy->promo_increment(max_contraction));
1.148 + gclog_or_tty->print_cr(" alignment " SIZE_FORMAT_HEX, gen_alignment);
1.149 + }
1.150 + assert(result_aligned <= max_contraction, "arithmetic is wrong");
1.151 + return result_aligned;
1.152 +}
