1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/gc_implementation/parallelScavenge/asPSOldGen.cpp Sat Dec 01 00:00:00 2007 +0000
1.3 @@ -0,0 +1,135 @@
1.4 +/*
1.5 + * Copyright 2003-2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.23 + * CA 95054 USA or visit www.sun.com if you need additional information or
1.24 + * have any questions.
1.25 + *
1.26 + */
1.27 +
1.28 +# include "incls/_precompiled.incl"
1.29 +# include "incls/_asPSOldGen.cpp.incl"
1.30 +
1.31 +// Whereas PSOldGen takes the maximum size of the generation
1.32 +// (which doesn't change in the case of PSOldGen) as a parameter,
1.33 +// ASPSOldGen takes the upper limit on the size of
1.34 +// the generation as a parameter. In ASPSOldGen the
1.35 +// maximum size of the generation can change as the boundary
1.36 +// moves. The "maximum size of the generation" is still a valid
1.37 +// concept since the generation can grow and shrink within that
1.38 +// maximum. There are lots of useful checks that use that
1.39 +// maximum. In PSOldGen the method max_gen_size() returns
1.40 +// _max_gen_size (as set by the PSOldGen constructor). This
1.41 +// is how it always worked. In ASPSOldGen max_gen_size()
1.42 +// returned the size of the reserved space for the generation.
1.43 +// That can change as the boundary moves. Below the limit of
1.44 +// the size of the generation is passed to the PSOldGen constructor
1.45 +// for "_max_gen_size" (have to pass something) but it is not used later.
1.46 +//
1.47 +ASPSOldGen::ASPSOldGen(size_t initial_size,
1.48 + size_t min_size,
1.49 + size_t size_limit,
1.50 + const char* gen_name,
1.51 + int level) :
1.52 + PSOldGen(initial_size, min_size, size_limit, gen_name, level),
1.53 + _gen_size_limit(size_limit)
1.54 +
1.55 +{}
1.56 +
1.57 +ASPSOldGen::ASPSOldGen(PSVirtualSpace* vs,
1.58 + size_t initial_size,
1.59 + size_t min_size,
1.60 + size_t size_limit,
1.61 + const char* gen_name,
1.62 + int level) :
1.63 + PSOldGen(initial_size, min_size, size_limit, gen_name, level),
1.64 + _gen_size_limit(size_limit)
1.65 +
1.66 +{
1.67 + _virtual_space = vs;
1.68 +}
1.69 +
1.70 +void ASPSOldGen::reset_after_change() {
1.71 + _reserved = MemRegion((HeapWord*)virtual_space()->low_boundary(),
1.72 + (HeapWord*)virtual_space()->high_boundary());
1.73 + post_resize();
1.74 +}
1.75 +
1.76 +
1.77 +size_t ASPSOldGen::available_for_expansion() {
1.78 + assert(virtual_space()->is_aligned(gen_size_limit()), "not aligned");
1.79 + assert(gen_size_limit() >= virtual_space()->committed_size(), "bad gen size");
1.80 +
1.81 + ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
1.82 + size_t result = gen_size_limit() - virtual_space()->committed_size();
1.83 + size_t result_aligned = align_size_down(result, heap->old_gen_alignment());
1.84 + return result_aligned;
1.85 +}
1.86 +
1.87 +size_t ASPSOldGen::available_for_contraction() {
1.88 + size_t uncommitted_bytes = virtual_space()->uncommitted_size();
1.89 + if (uncommitted_bytes != 0) {
1.90 + return uncommitted_bytes;
1.91 + }
1.92 +
1.93 + ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
1.94 + const size_t gen_alignment = heap->old_gen_alignment();
1.95 + PSAdaptiveSizePolicy* policy = heap->size_policy();
1.96 + const size_t working_size =
1.97 + used_in_bytes() + (size_t) policy->avg_promoted()->padded_average();
1.98 + const size_t working_aligned = align_size_up(working_size, gen_alignment);
1.99 + const size_t working_or_min = MAX2(working_aligned, min_gen_size());
1.100 + if (working_or_min > reserved().byte_size()) {
1.101 + // If the used or minimum gen size (aligned up) is greater
1.102 + // than the total reserved size, then the space available
1.103 + // for contraction should (after proper alignment) be 0
1.104 + return 0;
1.105 + }
1.106 + const size_t max_contraction =
1.107 + reserved().byte_size() - working_or_min;
1.108 +
1.109 + // Use the "increment" fraction instead of the "decrement" fraction
1.110 + // to allow the other gen to expand more aggressively. The
1.111 + // "decrement" fraction is conservative because its intent is to
1.112 + // only reduce the footprint.
1.113 +
1.114 + size_t result = policy->promo_increment_aligned_down(max_contraction);
1.115 + // Also adjust for inter-generational alignment
1.116 + size_t result_aligned = align_size_down(result, gen_alignment);
1.117 + if (PrintAdaptiveSizePolicy && Verbose) {
1.118 + gclog_or_tty->print_cr("\nASPSOldGen::available_for_contraction:"
1.119 + " %d K / 0x%x", result_aligned/K, result_aligned);
1.120 + gclog_or_tty->print_cr(" reserved().byte_size() %d K / 0x%x ",
1.121 + reserved().byte_size()/K, reserved().byte_size());
1.122 + size_t working_promoted = (size_t) policy->avg_promoted()->padded_average();
1.123 + gclog_or_tty->print_cr(" padded promoted %d K / 0x%x",
1.124 + working_promoted/K, working_promoted);
1.125 + gclog_or_tty->print_cr(" used %d K / 0x%x",
1.126 + used_in_bytes()/K, used_in_bytes());
1.127 + gclog_or_tty->print_cr(" min_gen_size() %d K / 0x%x",
1.128 + min_gen_size()/K, min_gen_size());
1.129 + gclog_or_tty->print_cr(" max_contraction %d K / 0x%x",
1.130 + max_contraction/K, max_contraction);
1.131 + gclog_or_tty->print_cr(" without alignment %d K / 0x%x",
1.132 + policy->promo_increment(max_contraction)/K,
1.133 + policy->promo_increment(max_contraction));
1.134 + gclog_or_tty->print_cr(" alignment 0x%x", gen_alignment);
1.135 + }
1.136 + assert(result_aligned <= max_contraction, "arithmetic is wrong");
1.137 + return result_aligned;
1.138 +}
