| /* |
| * Copyright (c) 2003, 2013, 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_implementation/parallelScavenge/adjoiningGenerations.hpp" |
| #include "gc_implementation/parallelScavenge/adjoiningVirtualSpaces.hpp" |
| #include "gc_implementation/parallelScavenge/generationSizer.hpp" |
| #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp" |
| |
| // If boundary moving is being used, create the young gen and old |
| // gen with ASPSYoungGen and ASPSOldGen, respectively. Revert to |
| // the old behavior otherwise (with PSYoungGen and PSOldGen). |
| |
| AdjoiningGenerations::AdjoiningGenerations(ReservedSpace old_young_rs, |
| GenerationSizer* policy, |
| size_t alignment) : |
| _virtual_spaces(old_young_rs, policy->min_gen1_size(), |
| policy->min_gen0_size(), alignment) { |
| size_t init_low_byte_size = policy->initial_gen1_size(); |
| size_t min_low_byte_size = policy->min_gen1_size(); |
| size_t max_low_byte_size = policy->max_gen1_size(); |
| size_t init_high_byte_size = policy->initial_gen0_size(); |
| size_t min_high_byte_size = policy->min_gen0_size(); |
| size_t max_high_byte_size = policy->max_gen0_size(); |
| |
| assert(min_low_byte_size <= init_low_byte_size && |
| init_low_byte_size <= max_low_byte_size, "Parameter check"); |
| assert(min_high_byte_size <= init_high_byte_size && |
| init_high_byte_size <= max_high_byte_size, "Parameter check"); |
| // Create the generations differently based on the option to |
| // move the boundary. |
| if (UseAdaptiveGCBoundary) { |
| // Initialize the adjoining virtual spaces. Then pass the |
| // a virtual to each generation for initialization of the |
| // generation. |
| |
| // Does the actual creation of the virtual spaces |
| _virtual_spaces.initialize(max_low_byte_size, |
| init_low_byte_size, |
| init_high_byte_size); |
| |
| // Place the young gen at the high end. Passes in the virtual space. |
| _young_gen = new ASPSYoungGen(_virtual_spaces.high(), |
| _virtual_spaces.high()->committed_size(), |
| min_high_byte_size, |
| _virtual_spaces.high_byte_size_limit()); |
| |
| // Place the old gen at the low end. Passes in the virtual space. |
| _old_gen = new ASPSOldGen(_virtual_spaces.low(), |
| _virtual_spaces.low()->committed_size(), |
| min_low_byte_size, |
| _virtual_spaces.low_byte_size_limit(), |
| "old", 1); |
| |
| young_gen()->initialize_work(); |
| assert(young_gen()->reserved().byte_size() <= young_gen()->gen_size_limit(), |
| "Consistency check"); |
| assert(old_young_rs.size() >= young_gen()->gen_size_limit(), |
| "Consistency check"); |
| |
| old_gen()->initialize_work("old", 1); |
| assert(old_gen()->reserved().byte_size() <= old_gen()->gen_size_limit(), |
| "Consistency check"); |
| assert(old_young_rs.size() >= old_gen()->gen_size_limit(), |
| "Consistency check"); |
| } else { |
| |
| // Layout the reserved space for the generations. |
| ReservedSpace old_rs = |
| virtual_spaces()->reserved_space().first_part(max_low_byte_size); |
| ReservedSpace heap_rs = |
| virtual_spaces()->reserved_space().last_part(max_low_byte_size); |
| ReservedSpace young_rs = heap_rs.first_part(max_high_byte_size); |
| assert(young_rs.size() == heap_rs.size(), "Didn't reserve all of the heap"); |
| |
| // Create the generations. Virtual spaces are not passed in. |
| _young_gen = new PSYoungGen(init_high_byte_size, |
| min_high_byte_size, |
| max_high_byte_size); |
| _old_gen = new PSOldGen(init_low_byte_size, |
| min_low_byte_size, |
| max_low_byte_size, |
| "old", 1); |
| |
| // The virtual spaces are created by the initialization of the gens. |
| _young_gen->initialize(young_rs, alignment); |
| assert(young_gen()->gen_size_limit() == young_rs.size(), |
| "Consistency check"); |
| _old_gen->initialize(old_rs, alignment, "old", 1); |
| assert(old_gen()->gen_size_limit() == old_rs.size(), "Consistency check"); |
| } |
| } |
| |
| size_t AdjoiningGenerations::reserved_byte_size() { |
| return virtual_spaces()->reserved_space().size(); |
| } |
| |
| |
| // Make checks on the current sizes of the generations and |
| // the constraints on the sizes of the generations. Push |
| // up the boundary within the constraints. A partial |
| // push can occur. |
| void AdjoiningGenerations::request_old_gen_expansion(size_t expand_in_bytes) { |
| assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check"); |
| |
| assert_lock_strong(ExpandHeap_lock); |
| assert_locked_or_safepoint(Heap_lock); |
| |
| // These sizes limit the amount the boundaries can move. Effectively, |
| // the generation says how much it is willing to yield to the other |
| // generation. |
| const size_t young_gen_available = young_gen()->available_for_contraction(); |
| const size_t old_gen_available = old_gen()->available_for_expansion(); |
| const size_t alignment = virtual_spaces()->alignment(); |
| size_t change_in_bytes = MIN3(young_gen_available, |
| old_gen_available, |
| align_size_up_(expand_in_bytes, alignment)); |
| |
| if (change_in_bytes == 0) { |
| return; |
| } |
| |
| if (TraceAdaptiveGCBoundary) { |
| gclog_or_tty->print_cr("Before expansion of old gen with boundary move"); |
| gclog_or_tty->print_cr(" Requested change: 0x%x Attempted change: 0x%x", |
| expand_in_bytes, change_in_bytes); |
| if (!PrintHeapAtGC) { |
| Universe::print_on(gclog_or_tty); |
| } |
| gclog_or_tty->print_cr(" PSOldGen max size: " SIZE_FORMAT "K", |
| old_gen()->max_gen_size()/K); |
| } |
| |
| // Move the boundary between the generations up (smaller young gen). |
| if (virtual_spaces()->adjust_boundary_up(change_in_bytes)) { |
| young_gen()->reset_after_change(); |
| old_gen()->reset_after_change(); |
| } |
| |
| // The total reserved for the generations should match the sum |
| // of the two even if the boundary is moving. |
| assert(reserved_byte_size() == |
| old_gen()->max_gen_size() + young_gen()->max_size(), |
| "Space is missing"); |
| young_gen()->space_invariants(); |
| old_gen()->space_invariants(); |
| |
| if (TraceAdaptiveGCBoundary) { |
| gclog_or_tty->print_cr("After expansion of old gen with boundary move"); |
| if (!PrintHeapAtGC) { |
| Universe::print_on(gclog_or_tty); |
| } |
| gclog_or_tty->print_cr(" PSOldGen max size: " SIZE_FORMAT "K", |
| old_gen()->max_gen_size()/K); |
| } |
| } |
| |
| // See comments on request_old_gen_expansion() |
| bool AdjoiningGenerations::request_young_gen_expansion(size_t expand_in_bytes) { |
| assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check"); |
| |
| // If eden is not empty, the boundary can be moved but no advantage |
| // can be made of the move since eden cannot be moved. |
| if (!young_gen()->eden_space()->is_empty()) { |
| return false; |
| } |
| |
| |
| bool result = false; |
| const size_t young_gen_available = young_gen()->available_for_expansion(); |
| const size_t old_gen_available = old_gen()->available_for_contraction(); |
| const size_t alignment = virtual_spaces()->alignment(); |
| size_t change_in_bytes = MIN3(young_gen_available, |
| old_gen_available, |
| align_size_up_(expand_in_bytes, alignment)); |
| |
| if (change_in_bytes == 0) { |
| return false; |
| } |
| |
| if (TraceAdaptiveGCBoundary) { |
| gclog_or_tty->print_cr("Before expansion of young gen with boundary move"); |
| gclog_or_tty->print_cr(" Requested change: 0x%x Attempted change: 0x%x", |
| expand_in_bytes, change_in_bytes); |
| if (!PrintHeapAtGC) { |
| Universe::print_on(gclog_or_tty); |
| } |
| gclog_or_tty->print_cr(" PSYoungGen max size: " SIZE_FORMAT "K", |
| young_gen()->max_size()/K); |
| } |
| |
| // Move the boundary between the generations down (smaller old gen). |
| MutexLocker x(ExpandHeap_lock); |
| if (virtual_spaces()->adjust_boundary_down(change_in_bytes)) { |
| young_gen()->reset_after_change(); |
| old_gen()->reset_after_change(); |
| result = true; |
| } |
| |
| // The total reserved for the generations should match the sum |
| // of the two even if the boundary is moving. |
| assert(reserved_byte_size() == |
| old_gen()->max_gen_size() + young_gen()->max_size(), |
| "Space is missing"); |
| young_gen()->space_invariants(); |
| old_gen()->space_invariants(); |
| |
| if (TraceAdaptiveGCBoundary) { |
| gclog_or_tty->print_cr("After expansion of young gen with boundary move"); |
| if (!PrintHeapAtGC) { |
| Universe::print_on(gclog_or_tty); |
| } |
| gclog_or_tty->print_cr(" PSYoungGen max size: " SIZE_FORMAT "K", |
| young_gen()->max_size()/K); |
| } |
| |
| return result; |
| } |
| |
| // Additional space is needed in the old generation. Try to move the boundary |
| // up to meet the need. Moves boundary up only |
| void AdjoiningGenerations::adjust_boundary_for_old_gen_needs( |
| size_t desired_free_space) { |
| assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check"); |
| |
| // Stress testing. |
| if (PSAdaptiveSizePolicyResizeVirtualSpaceAlot == 1) { |
| MutexLocker x(ExpandHeap_lock); |
| request_old_gen_expansion(virtual_spaces()->alignment() * 3 / 2); |
| } |
| |
| // Expand only if the entire generation is already committed. |
| if (old_gen()->virtual_space()->uncommitted_size() == 0) { |
| if (old_gen()->free_in_bytes() < desired_free_space) { |
| MutexLocker x(ExpandHeap_lock); |
| request_old_gen_expansion(desired_free_space); |
| } |
| } |
| } |
| |
| // See comment on adjust_boundary_for_old_gen_needss(). |
| // Adjust boundary down only. |
| void AdjoiningGenerations::adjust_boundary_for_young_gen_needs(size_t eden_size, |
| size_t survivor_size) { |
| |
| assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check"); |
| |
| // Stress testing. |
| if (PSAdaptiveSizePolicyResizeVirtualSpaceAlot == 0) { |
| request_young_gen_expansion(virtual_spaces()->alignment() * 3 / 2); |
| eden_size = young_gen()->eden_space()->capacity_in_bytes(); |
| } |
| |
| // Expand only if the entire generation is already committed. |
| if (young_gen()->virtual_space()->uncommitted_size() == 0) { |
| size_t desired_size = eden_size + 2 * survivor_size; |
| const size_t committed = young_gen()->virtual_space()->committed_size(); |
| if (desired_size > committed) { |
| request_young_gen_expansion(desired_size - committed); |
| } |
| } |
| } |