1 /* 2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "gc_implementation/shared/ageTable.hpp" 27 #include "gc_implementation/shared/ageTableTracer.hpp" 28 #include "gc_implementation/shared/gcPolicyCounters.hpp" 29 #include "memory/collectorPolicy.hpp" 30 #include "memory/resourceArea.hpp" 31 #include "memory/sharedHeap.hpp" 32 #include "utilities/copy.hpp" 33 34 /* Copyright (c) 1992-2009 Oracle and/or its affiliates, and Stanford University. 35 See the LICENSE file for license information. */ 36 37 ageTable::ageTable(bool global) { 38 39 clear(); 40 41 if (UsePerfData && global) { 42 43 ResourceMark rm; 44 EXCEPTION_MARK; 45 46 const char* agetable_ns = "generation.0.agetable"; 47 const char* bytes_ns = PerfDataManager::name_space(agetable_ns, "bytes"); 48 49 for(int age = 0; age < table_size; age ++) { 50 char age_name[10]; 51 jio_snprintf(age_name, sizeof(age_name), "%2.2d", age); 52 const char* cname = PerfDataManager::counter_name(bytes_ns, age_name); 53 _perf_sizes[age] = PerfDataManager::create_variable(SUN_GC, cname, 54 PerfData::U_Bytes, 55 CHECK); 56 } 57 58 const char* cname = PerfDataManager::counter_name(agetable_ns, "size"); 59 PerfDataManager::create_constant(SUN_GC, cname, PerfData::U_None, 60 table_size, CHECK); 61 } 62 } 63 64 void ageTable::clear() { 65 for (size_t* p = sizes; p < sizes + table_size; ++p) { 66 *p = 0; 67 } 68 } 69 70 void ageTable::merge(ageTable* subTable) { 71 for (int i = 0; i < table_size; i++) { 72 sizes[i]+= subTable->sizes[i]; 73 } 74 } 75 76 void ageTable::merge_par(ageTable* subTable) { 77 for (int i = 0; i < table_size; i++) { 78 Atomic::add_ptr(subTable->sizes[i], &sizes[i]); 79 } 80 } 81 82 uint ageTable::compute_tenuring_threshold(size_t survivor_capacity, GCTracer &tracer) { 83 size_t desired_survivor_size = (size_t)((((double) survivor_capacity)*TargetSurvivorRatio)/100); 84 size_t total = 0; 85 uint age = 1; 86 assert(sizes[0] == 0, "no objects with age zero should be recorded"); 87 while (age < table_size) { 88 total += sizes[age]; 89 // check if including objects of age 'age' made us pass the desired 90 // size, if so 'age' is the new threshold 91 if (total > desired_survivor_size) break; 92 age++; 93 } 94 uint result = age < MaxTenuringThreshold ? age : MaxTenuringThreshold; 95 96 if (PrintTenuringDistribution || UsePerfData || AgeTableTracer::is_tenuring_distribution_event_enabled()) { 97 98 if (PrintTenuringDistribution) { 99 gclog_or_tty->cr(); 100 gclog_or_tty->print_cr("Desired survivor size " SIZE_FORMAT " bytes, new threshold %u (max %u)", 101 desired_survivor_size*oopSize, result, (int) MaxTenuringThreshold); 102 } 103 104 total = 0; 105 age = 1; 106 while (age < table_size) { 107 total += sizes[age]; 108 if (sizes[age] > 0) { 109 if (PrintTenuringDistribution) { 110 gclog_or_tty->print_cr("- age %3u: " SIZE_FORMAT_W(10) " bytes, " SIZE_FORMAT_W(10) " total", 111 age, sizes[age]*oopSize, total*oopSize); 112 } 113 } 114 AgeTableTracer::send_tenuring_distribution_event(age, wordSize * oopSize, tracer); 115 if (UsePerfData) { 116 _perf_sizes[age]->set_value(sizes[age]*oopSize); 117 } 118 age++; 119 } 120 if (UsePerfData) { 121 SharedHeap* sh = SharedHeap::heap(); 122 CollectorPolicy* policy = sh->collector_policy(); 123 GCPolicyCounters* gc_counters = policy->counters(); 124 gc_counters->tenuring_threshold()->set_value(result); 125 gc_counters->desired_survivor_size()->set_value( 126 desired_survivor_size*oopSize); 127 } 128 } 129 130 return result; 131 }