1 /* 2 * Copyright (c) 2020, Amazon.com, Inc. 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 #ifndef SHARE_VM_GC_G1_G1OLDGENALLOCATIONTRACKER_HPP 26 #define SHARE_VM_GC_G1_G1OLDGENALLOCATIONTRACKER_HPP 27 28 #include "gc/g1/heapRegion.hpp" 29 #include "memory/allocation.hpp" 30 31 class G1AdaptiveIHOPControl; 32 33 // Track allocation details in the old generation. 34 class G1OldGenAllocationTracker : public CHeapObj<mtGC> { 35 // New bytes allocated in old gen between the end of the last GC and 36 // the end of the GC before that. This includes humongous object allocation. 37 size_t _last_period_old_bytes; 38 // New bytes allocated in humongous regions between the end of the last GC and 39 // the end of the GC before that. 40 size_t _last_period_humongous_bytes; 41 42 size_t _humongous_bytes_after_last_gc; 43 size_t _humongous_bytes_after_penultimate_gc; 44 45 size_t _allocated_bytes_since_last_gc; 46 size_t _allocated_humongous_bytes_since_last_gc; 47 48 public: 49 G1OldGenAllocationTracker(); 50 // Add the given number of bytes to the total number of allocated bytes in the old gen. 51 void add_allocated_bytes_since_last_gc(size_t bytes) { _allocated_bytes_since_last_gc += bytes; } 52 53 void add_allocated_humongous_bytes_since_last_gc(size_t bytes) { 54 _allocated_humongous_bytes_since_last_gc += bytes; 55 _allocated_bytes_since_last_gc += bytes; 56 } 57 58 // Record a humongous allocation during a collection pause. 59 // In g1CollectedHeap, when a humongous allocation fails, the heap will attempt 60 // to trigger a GC and try to allocate the required bytes during it. These bytes 61 // are then not counted in any mutator period but as survived bytes after GC. 62 // Otherwise, they would distort our estimation for how many humongous bytes are 63 // freed in a mutator period. 64 void record_collection_pause_humongous_allocation(size_t bytes) { 65 _humongous_bytes_after_last_gc += bytes; 66 } 67 68 size_t last_period_old_bytes() const { return _last_period_old_bytes; } 69 70 // Reset stats after a collection. 71 void reset_after_gc(size_t humongous_bytes_after_gc); 72 73 // This is used by Adaptive IHOP to sample the old gen allocation rate. 74 // Different from the regular old gen allocation rate, this method considers the 75 // humongous objects that can be reclaimed early by young GCs. Since we cannot 76 // track the life cycle of individual humongous objects, we assume that such 77 // objects were all newly allocated and not survivors, unless more were 78 // reclaimed than allocated. 79 size_t last_period_net_survived_old_bytes() const; 80 }; 81 82 #endif // SHARE_VM_GC_G1_G1OLDGENALLOCATIONTRACKER_HPP