1 /* 2 * Copyright (c) 1997, 2016, 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.inline.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 "oops/oop.inline.hpp" 33 #include "utilities/copy.hpp" 34 35 /* Copyright (c) 1992, 2016, Oracle and/or its affiliates, and Stanford University. 36 See the LICENSE file for license information. */ 37 38 AgeTable::AgeTable(bool global) { 39 40 clear(); 41 42 if (UsePerfData && global) { 43 44 ResourceMark rm; 45 EXCEPTION_MARK; 46 47 const char* agetable_ns = "generation.0.agetable"; 48 const char* bytes_ns = PerfDataManager::name_space(agetable_ns, "bytes"); 49 50 for(int age = 0; age < table_size; age ++) { 51 char age_name[10]; 52 jio_snprintf(age_name, sizeof(age_name), "%2.2d", age); 53 const char* cname = PerfDataManager::counter_name(bytes_ns, age_name); 54 _perf_sizes[age] = PerfDataManager::create_variable(SUN_GC, cname, 55 PerfData::U_Bytes, 56 CHECK); 57 } 58 59 const char* cname = PerfDataManager::counter_name(agetable_ns, "size"); 60 PerfDataManager::create_constant(SUN_GC, cname, PerfData::U_None, 61 table_size, CHECK); 62 } 63 } 64 65 void AgeTable::clear() { 66 for (size_t* p = sizes; p < sizes + table_size; ++p) { 67 *p = 0; 68 } 69 } 70 71 void AgeTable::merge(AgeTable* subTable) { 72 for (int i = 0; i < table_size; i++) { 73 sizes[i]+= subTable->sizes[i]; 74 } 75 } 76 77 uint AgeTable::compute_tenuring_threshold(size_t survivor_capacity, GCPolicyCounters* gc_counters) { 78 size_t desired_survivor_size = (size_t)((((double) survivor_capacity)*TargetSurvivorRatio)/100); 79 uint result; 80 81 if (AlwaysTenure || NeverTenure) { 82 assert(MaxTenuringThreshold == 0 || MaxTenuringThreshold == markOopDesc::max_age + 1, 83 "MaxTenuringThreshold should be 0 or markOopDesc::max_age + 1, but is " UINTX_FORMAT, MaxTenuringThreshold); 84 result = MaxTenuringThreshold; 85 } else { 86 size_t total = 0; 87 uint age = 1; 88 assert(sizes[0] == 0, "no objects with age zero should be recorded"); 89 while (age < table_size) { 90 total += sizes[age]; 91 // check if including objects of age 'age' made us pass the desired 92 // size, if so 'age' is the new threshold 93 if (total > desired_survivor_size) break; 94 age++; 95 } 96 result = age < MaxTenuringThreshold ? age : MaxTenuringThreshold; 97 } 98 99 100 log_debug(gc, age)("Desired survivor size " SIZE_FORMAT " bytes, new threshold " UINTX_FORMAT " (max threshold " UINTX_FORMAT ")", 101 desired_survivor_size*oopSize, (uintx) result, MaxTenuringThreshold); 102 103 if (log_is_enabled(Trace, gc, age) || UsePerfData) { 104 size_t total = 0; 105 uint age = 1; 106 while (age < table_size) { 107 total += sizes[age]; 108 if (sizes[age] > 0) { 109 log_trace(gc, age)("- age %3u: " SIZE_FORMAT_W(10) " bytes, " SIZE_FORMAT_W(10) " total", 110 age, sizes[age]*oopSize, total*oopSize); 111 } 112 if (UsePerfData) { 113 _perf_sizes[age]->set_value(sizes[age]*oopSize); 114 } 115 age++; 116 } 117 if (UsePerfData) { 118 gc_counters->tenuring_threshold()->set_value(result); 119 gc_counters->desired_survivor_size()->set_value( 120 desired_survivor_size*oopSize); 121 } 122 } 123 124 return result; 125 }