1 /* 2 * Copyright (c) 1997, 2015, 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/shared/ageTable.hpp" 27 #include "gc/shared/collectedHeap.hpp" 28 #include "gc/shared/collectorPolicy.hpp" 29 #include "gc/shared/gcPolicyCounters.hpp" 30 #include "memory/resourceArea.hpp" 31 #include "logging/log.hpp" 32 #include "utilities/copy.hpp" 33 34 /* Copyright (c) 1992, 2015, 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 uint AgeTable::compute_tenuring_threshold(size_t survivor_capacity, GCPolicyCounters* gc_counters) { 77 size_t desired_survivor_size = (size_t)((((double) survivor_capacity)*TargetSurvivorRatio)/100); 78 uint result; 79 80 if (AlwaysTenure || NeverTenure) { 81 assert(MaxTenuringThreshold == 0 || MaxTenuringThreshold == markOopDesc::max_age + 1, 82 "MaxTenuringThreshold should be 0 or markOopDesc::max_age + 1, but is " UINTX_FORMAT, MaxTenuringThreshold); 83 result = MaxTenuringThreshold; 84 } else { 85 size_t total = 0; 86 uint age = 1; 87 assert(sizes[0] == 0, "no objects with age zero should be recorded"); 88 while (age < table_size) { 89 total += sizes[age]; 90 // check if including objects of age 'age' made us pass the desired 91 // size, if so 'age' is the new threshold 92 if (total > desired_survivor_size) break; 93 age++; 94 } 95 result = age < MaxTenuringThreshold ? age : MaxTenuringThreshold; 96 } 97 98 99 log_debug(gc, age)("Desired survivor size " SIZE_FORMAT " bytes, new threshold " UINTX_FORMAT " (max threshold " UINTX_FORMAT ")", 100 desired_survivor_size*oopSize, (uintx) result, MaxTenuringThreshold); 101 102 if (log_is_enabled(Trace, gc, age) || UsePerfData) { 103 size_t total = 0; 104 uint age = 1; 105 while (age < table_size) { 106 total += sizes[age]; 107 if (sizes[age] > 0) { 108 log_trace(gc, age)("- age %3u: " SIZE_FORMAT_W(10) " bytes, " SIZE_FORMAT_W(10) " total", 109 age, sizes[age]*oopSize, total*oopSize); 110 } 111 if (UsePerfData) { 112 _perf_sizes[age]->set_value(sizes[age]*oopSize); 113 } 114 age++; 115 } 116 if (UsePerfData) { 117 gc_counters->tenuring_threshold()->set_value(result); 118 gc_counters->desired_survivor_size()->set_value( 119 desired_survivor_size*oopSize); 120 } 121 } 122 123 return result; 124 }