| /* |
| * Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved. |
| * 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/asPSOldGen.hpp" |
| #include "gc/parallel/parallelScavengeHeap.hpp" |
| #include "gc/parallel/psAdaptiveSizePolicy.hpp" |
| #include "gc/parallel/psMarkSweepDecorator.hpp" |
| #include "gc/shared/cardTableModRefBS.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "runtime/java.hpp" |
| |
| // Whereas PSOldGen takes the maximum size of the generation |
| // (which doesn't change in the case of PSOldGen) as a parameter, |
| // ASPSOldGen takes the upper limit on the size of |
| // the generation as a parameter. In ASPSOldGen the |
| // maximum size of the generation can change as the boundary |
| // moves. The "maximum size of the generation" is still a valid |
| // concept since the generation can grow and shrink within that |
| // maximum. There are lots of useful checks that use that |
| // maximum. In PSOldGen the method max_gen_size() returns |
| // _max_gen_size (as set by the PSOldGen constructor). This |
| // is how it always worked. In ASPSOldGen max_gen_size() |
| // returned the size of the reserved space for the generation. |
| // That can change as the boundary moves. Below the limit of |
| // the size of the generation is passed to the PSOldGen constructor |
| // for "_max_gen_size" (have to pass something) but it is not used later. |
| // |
| ASPSOldGen::ASPSOldGen(size_t initial_size, |
| size_t min_size, |
| size_t size_limit, |
| const char* gen_name, |
| int level) : |
| PSOldGen(initial_size, min_size, size_limit, gen_name, level), |
| _gen_size_limit(size_limit) |
| {} |
| |
| ASPSOldGen::ASPSOldGen(PSVirtualSpace* vs, |
| size_t initial_size, |
| size_t min_size, |
| size_t size_limit, |
| const char* gen_name, |
| int level) : |
| PSOldGen(initial_size, min_size, size_limit, gen_name, level), |
| _gen_size_limit(size_limit) |
| { |
| _virtual_space = vs; |
| } |
| |
| void ASPSOldGen::initialize_work(const char* perf_data_name, int level) { |
| PSOldGen::initialize_work(perf_data_name, level); |
| |
| // The old gen can grow to gen_size_limit(). _reserve reflects only |
| // the current maximum that can be committed. |
| assert(_reserved.byte_size() <= gen_size_limit(), "Consistency check"); |
| |
| initialize_performance_counters(perf_data_name, level); |
| } |
| |
| void ASPSOldGen::reset_after_change() { |
| _reserved = MemRegion((HeapWord*)virtual_space()->low_boundary(), |
| (HeapWord*)virtual_space()->high_boundary()); |
| post_resize(); |
| } |
| |
| |
| size_t ASPSOldGen::available_for_expansion() { |
| assert(virtual_space()->is_aligned(gen_size_limit()), "not aligned"); |
| assert(gen_size_limit() >= virtual_space()->committed_size(), "bad gen size"); |
| |
| ParallelScavengeHeap* heap = ParallelScavengeHeap::heap(); |
| size_t result = gen_size_limit() - virtual_space()->committed_size(); |
| size_t result_aligned = align_size_down(result, heap->generation_alignment()); |
| return result_aligned; |
| } |
| |
| size_t ASPSOldGen::available_for_contraction() { |
| size_t uncommitted_bytes = virtual_space()->uncommitted_size(); |
| if (uncommitted_bytes != 0) { |
| return uncommitted_bytes; |
| } |
| |
| ParallelScavengeHeap* heap = ParallelScavengeHeap::heap(); |
| const size_t gen_alignment = heap->generation_alignment(); |
| PSAdaptiveSizePolicy* policy = heap->size_policy(); |
| const size_t working_size = |
| used_in_bytes() + (size_t) policy->avg_promoted()->padded_average(); |
| const size_t working_aligned = align_size_up(working_size, gen_alignment); |
| const size_t working_or_min = MAX2(working_aligned, min_gen_size()); |
| if (working_or_min > reserved().byte_size()) { |
| // If the used or minimum gen size (aligned up) is greater |
| // than the total reserved size, then the space available |
| // for contraction should (after proper alignment) be 0 |
| return 0; |
| } |
| const size_t max_contraction = |
| reserved().byte_size() - working_or_min; |
| |
| // Use the "increment" fraction instead of the "decrement" fraction |
| // to allow the other gen to expand more aggressively. The |
| // "decrement" fraction is conservative because its intent is to |
| // only reduce the footprint. |
| |
| size_t result = policy->promo_increment_aligned_down(max_contraction); |
| // Also adjust for inter-generational alignment |
| size_t result_aligned = align_size_down(result, gen_alignment); |
| |
| LogHandle(gc, ergo) log; |
| if (log.is_trace()) { |
| size_t working_promoted = (size_t) policy->avg_promoted()->padded_average(); |
| size_t promo_increment = policy->promo_increment(max_contraction); |
| log.trace("ASPSOldGen::available_for_contraction: " SIZE_FORMAT " K / " SIZE_FORMAT_HEX, result_aligned/K, result_aligned); |
| log.trace(" reserved().byte_size() " SIZE_FORMAT " K / " SIZE_FORMAT_HEX, reserved().byte_size()/K, reserved().byte_size()); |
| log.trace(" padded promoted " SIZE_FORMAT " K / " SIZE_FORMAT_HEX, working_promoted/K, working_promoted); |
| log.trace(" used " SIZE_FORMAT " K / " SIZE_FORMAT_HEX, used_in_bytes()/K, used_in_bytes()); |
| log.trace(" min_gen_size() " SIZE_FORMAT " K / " SIZE_FORMAT_HEX, min_gen_size()/K, min_gen_size()); |
| log.trace(" max_contraction " SIZE_FORMAT " K / " SIZE_FORMAT_HEX, max_contraction/K, max_contraction); |
| log.trace(" without alignment " SIZE_FORMAT " K / " SIZE_FORMAT_HEX, promo_increment/K, promo_increment); |
| log.trace(" alignment " SIZE_FORMAT_HEX, gen_alignment); |
| } |
| |
| assert(result_aligned <= max_contraction, "arithmetic is wrong"); |
| return result_aligned; |
| } |