Mercurial > hg > graal-jvmci-8
view src/share/vm/gc_implementation/g1/survRateGroup.cpp @ 1886:72a161e62cc4
6991377: G1: race between concurrent refinement and humongous object allocation
Summary: There is a race between the concurrent refinement threads and the humongous object allocation that can cause the concurrent refinement threads to corrupt the part of the BOT that it is being initialized by the humongous object allocation operation. The solution is to do the humongous object allocation in careful steps to ensure that the concurrent refinement threads always have a consistent view over the BOT, region contents, and top. The fix includes some very minor tidying up in sparsePRT.
Reviewed-by: jcoomes, johnc, ysr
author | tonyp |
---|---|
date | Sat, 16 Oct 2010 17:12:19 -0400 |
parents | c18cbe5936b8 |
children | f95d63e2154a |
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/* * Copyright (c) 2001, 2010, 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 "incls/_precompiled.incl" #include "incls/_survRateGroup.cpp.incl" SurvRateGroup::SurvRateGroup(G1CollectorPolicy* g1p, const char* name, size_t summary_surv_rates_len) : _g1p(g1p), _name(name), _summary_surv_rates_len(summary_surv_rates_len), _summary_surv_rates_max_len(0), _summary_surv_rates(NULL), _surv_rate(NULL), _accum_surv_rate_pred(NULL), _surv_rate_pred(NULL) { reset(); if (summary_surv_rates_len > 0) { size_t length = summary_surv_rates_len; _summary_surv_rates = NEW_C_HEAP_ARRAY(NumberSeq*, length); if (_summary_surv_rates == NULL) { vm_exit_out_of_memory(sizeof(NumberSeq*) * length, "Not enough space for surv rate summary"); } for (size_t i = 0; i < length; ++i) _summary_surv_rates[i] = new NumberSeq(); } start_adding_regions(); } void SurvRateGroup::reset() { _all_regions_allocated = 0; _setup_seq_num = 0; _stats_arrays_length = 0; _accum_surv_rate = 0.0; _last_pred = 0.0; // the following will set up the arrays with length 1 _region_num = 1; stop_adding_regions(); guarantee( _stats_arrays_length == 1, "invariant" ); guarantee( _surv_rate_pred[0] != NULL, "invariant" ); _surv_rate_pred[0]->add(0.4); all_surviving_words_recorded(false); _region_num = 0; } void SurvRateGroup::start_adding_regions() { _setup_seq_num = _stats_arrays_length; _region_num = 0; _accum_surv_rate = 0.0; #if 0 gclog_or_tty->print_cr("[%s] start adding regions, seq num %d, length %d", _name, _setup_seq_num, _region_num); #endif // 0 } void SurvRateGroup::stop_adding_regions() { #if 0 gclog_or_tty->print_cr("[%s] stop adding regions, length %d", _name, _region_num); #endif // 0 if (_region_num > _stats_arrays_length) { double* old_surv_rate = _surv_rate; double* old_accum_surv_rate_pred = _accum_surv_rate_pred; TruncatedSeq** old_surv_rate_pred = _surv_rate_pred; _surv_rate = NEW_C_HEAP_ARRAY(double, _region_num); if (_surv_rate == NULL) { vm_exit_out_of_memory(sizeof(double) * _region_num, "Not enough space for surv rate array."); } _accum_surv_rate_pred = NEW_C_HEAP_ARRAY(double, _region_num); if (_accum_surv_rate_pred == NULL) { vm_exit_out_of_memory(sizeof(double) * _region_num, "Not enough space for accum surv rate pred array."); } _surv_rate_pred = NEW_C_HEAP_ARRAY(TruncatedSeq*, _region_num); if (_surv_rate == NULL) { vm_exit_out_of_memory(sizeof(TruncatedSeq*) * _region_num, "Not enough space for surv rate pred array."); } for (size_t i = 0; i < _stats_arrays_length; ++i) _surv_rate_pred[i] = old_surv_rate_pred[i]; #if 0 gclog_or_tty->print_cr("[%s] stop adding regions, new seqs %d to %d", _name, _array_length, _region_num - 1); #endif // 0 for (size_t i = _stats_arrays_length; i < _region_num; ++i) { _surv_rate_pred[i] = new TruncatedSeq(10); // _surv_rate_pred[i]->add(last_pred); } _stats_arrays_length = _region_num; if (old_surv_rate != NULL) FREE_C_HEAP_ARRAY(double, old_surv_rate); if (old_accum_surv_rate_pred != NULL) FREE_C_HEAP_ARRAY(double, old_accum_surv_rate_pred); if (old_surv_rate_pred != NULL) FREE_C_HEAP_ARRAY(NumberSeq*, old_surv_rate_pred); } for (size_t i = 0; i < _stats_arrays_length; ++i) _surv_rate[i] = 0.0; } double SurvRateGroup::accum_surv_rate(size_t adjustment) { // we might relax this one in the future... guarantee( adjustment == 0 || adjustment == 1, "pre-condition" ); double ret = _accum_surv_rate; if (adjustment > 0) { TruncatedSeq* seq = get_seq(_region_num+1); double surv_rate = _g1p->get_new_prediction(seq); ret += surv_rate; } return ret; } int SurvRateGroup::next_age_index() { TruncatedSeq* seq = get_seq(_region_num); double surv_rate = _g1p->get_new_prediction(seq); _accum_surv_rate += surv_rate; ++_region_num; return (int) ++_all_regions_allocated; } void SurvRateGroup::record_surviving_words(int age_in_group, size_t surv_words) { guarantee( 0 <= age_in_group && (size_t) age_in_group < _region_num, "pre-condition" ); guarantee( _surv_rate[age_in_group] <= 0.00001, "should only update each slot once" ); double surv_rate = (double) surv_words / (double) HeapRegion::GrainWords; _surv_rate[age_in_group] = surv_rate; _surv_rate_pred[age_in_group]->add(surv_rate); if ((size_t)age_in_group < _summary_surv_rates_len) { _summary_surv_rates[age_in_group]->add(surv_rate); if ((size_t)(age_in_group+1) > _summary_surv_rates_max_len) _summary_surv_rates_max_len = age_in_group+1; } } void SurvRateGroup::all_surviving_words_recorded(bool propagate) { if (propagate && _region_num > 0) { // conservative double surv_rate = _surv_rate_pred[_region_num-1]->last(); #if 0 gclog_or_tty->print_cr("propagating %1.2lf from %d to %d", surv_rate, _curr_length, _array_length - 1); #endif // 0 for (size_t i = _region_num; i < _stats_arrays_length; ++i) { guarantee( _surv_rate[i] <= 0.00001, "the slot should not have been updated" ); _surv_rate_pred[i]->add(surv_rate); } } double accum = 0.0; double pred = 0.0; for (size_t i = 0; i < _stats_arrays_length; ++i) { pred = _g1p->get_new_prediction(_surv_rate_pred[i]); if (pred > 1.0) pred = 1.0; accum += pred; _accum_surv_rate_pred[i] = accum; // gclog_or_tty->print_cr("age %3d, accum %10.2lf", i, accum); } _last_pred = pred; } #ifndef PRODUCT void SurvRateGroup::print() { gclog_or_tty->print_cr("Surv Rate Group: %s (%d entries)", _name, _region_num); for (size_t i = 0; i < _region_num; ++i) { gclog_or_tty->print_cr(" age %4d surv rate %6.2lf %% pred %6.2lf %%", i, _surv_rate[i] * 100.0, _g1p->get_new_prediction(_surv_rate_pred[i]) * 100.0); } } void SurvRateGroup::print_surv_rate_summary() { size_t length = _summary_surv_rates_max_len; if (length == 0) return; gclog_or_tty->print_cr(""); gclog_or_tty->print_cr("%s Rate Summary (for up to age %d)", _name, length-1); gclog_or_tty->print_cr(" age range survival rate (avg) samples (avg)"); gclog_or_tty->print_cr(" ---------------------------------------------------------"); size_t index = 0; size_t limit = MIN2((int) length, 10); while (index < limit) { gclog_or_tty->print_cr(" %4d %6.2lf%% %6.2lf", index, _summary_surv_rates[index]->avg() * 100.0, (double) _summary_surv_rates[index]->num()); ++index; } gclog_or_tty->print_cr(" ---------------------------------------------------------"); int num = 0; double sum = 0.0; int samples = 0; while (index < length) { ++num; sum += _summary_surv_rates[index]->avg() * 100.0; samples += _summary_surv_rates[index]->num(); ++index; if (index == length || num % 10 == 0) { gclog_or_tty->print_cr(" %4d .. %4d %6.2lf%% %6.2lf", (index-1) / 10 * 10, index-1, sum / (double) num, (double) samples / (double) num); sum = 0.0; num = 0; samples = 0; } } gclog_or_tty->print_cr(" ---------------------------------------------------------"); } #endif // PRODUCT