1 /* 2 * Copyright (c) 1997, 2021, 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/ageTableTracer.hpp" 28 #include "gc/shared/collectedHeap.hpp" 29 #include "gc/shared/gc_globals.hpp" 30 #include "jvm.h" 31 #include "logging/log.hpp" 32 #include "memory/resourceArea.hpp" 33 #include "oops/oop.inline.hpp" 34 #include "runtime/perfData.hpp" 35 #include "utilities/copy.hpp" 36 37 /* Copyright (c) 1992, 2021, Oracle and/or its affiliates, and Stanford University. 38 See the LICENSE file for license information. */ 39 40 AgeTable::AgeTable(bool global) { 41 42 clear(); 43 44 if (UsePerfData && global) { 45 46 ResourceMark rm; 47 EXCEPTION_MARK; 48 49 const char* agetable_ns = "generation.0.agetable"; 50 const char* bytes_ns = PerfDataManager::name_space(agetable_ns, "bytes"); 51 52 for(int age = 0; age < table_size; age ++) { 53 char age_name[10]; 54 jio_snprintf(age_name, sizeof(age_name), "%2.2d", age); 55 const char* cname = PerfDataManager::counter_name(bytes_ns, age_name); 56 _perf_sizes[age] = PerfDataManager::create_variable(SUN_GC, cname, 57 PerfData::U_Bytes, 58 CHECK); 59 } 60 61 const char* cname = PerfDataManager::counter_name(agetable_ns, "size"); 62 PerfDataManager::create_constant(SUN_GC, cname, PerfData::U_None, 63 table_size, CHECK); 64 } 65 } 66 67 void AgeTable::clear() { 68 for (size_t* p = sizes; p < sizes + table_size; ++p) { 69 *p = 0; 70 } 71 } 72 73 void AgeTable::merge(AgeTable* subTable) { 74 for (int i = 0; i < table_size; i++) { 75 sizes[i]+= subTable->sizes[i]; 76 } 77 } 78 79 uint AgeTable::compute_tenuring_threshold(size_t desired_survivor_size) { 80 uint result; 81 82 if (AlwaysTenure || NeverTenure) { 83 assert(MaxTenuringThreshold == 0 || MaxTenuringThreshold == markWord::max_age + 1, 84 "MaxTenuringThreshold should be 0 or markWord::max_age + 1, but is " UINTX_FORMAT, MaxTenuringThreshold); 85 result = MaxTenuringThreshold; 86 } else { 87 size_t total = 0; 88 uint age = 1; 89 assert(sizes[0] == 0, "no objects with age zero should be recorded"); 90 while (age < table_size) { 91 total += sizes[age]; 92 // check if including objects of age 'age' made us pass the desired 93 // size, if so 'age' is the new threshold 94 if (total > desired_survivor_size) break; 95 age++; 96 } 97 result = age < MaxTenuringThreshold ? age : MaxTenuringThreshold; 98 } 99 100 101 log_debug(gc, age)("Desired survivor size " SIZE_FORMAT " bytes, new threshold " UINTX_FORMAT " (max threshold " UINTX_FORMAT ")", 102 desired_survivor_size * oopSize, (uintx) result, MaxTenuringThreshold); 103 104 return result; 105 } 106 107 void AgeTable::print_age_table(uint tenuring_threshold) { 108 if (log_is_enabled(Trace, gc, age) || UsePerfData || AgeTableTracer::is_tenuring_distribution_event_enabled()) { 109 log_trace(gc, age)("Age table with threshold %u (max threshold " UINTX_FORMAT ")", 110 tenuring_threshold, MaxTenuringThreshold); 111 112 size_t total = 0; 113 uint age = 1; 114 while (age < table_size) { 115 size_t wordSize = sizes[age]; 116 total += wordSize; 117 if (wordSize > 0) { 118 log_trace(gc, age)("- age %3u: " SIZE_FORMAT_W(10) " bytes, " SIZE_FORMAT_W(10) " total", 119 age, wordSize * oopSize, total * oopSize); 120 } 121 AgeTableTracer::send_tenuring_distribution_event(age, wordSize * oopSize); 122 if (UsePerfData) { 123 _perf_sizes[age]->set_value(wordSize * oopSize); 124 } 125 age++; 126 } 127 } 128 } 129