1 /* 2 * Copyright (c) 2001, 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 #ifndef SHARE_VM_GC_G1_CONCURRENTG1REFINE_HPP 26 #define SHARE_VM_GC_G1_CONCURRENTG1REFINE_HPP 27 28 #include "memory/allocation.hpp" 29 #include "utilities/globalDefinitions.hpp" 30 31 // Forward decl 32 class CardTableEntryClosure; 33 class ConcurrentG1RefineThread; 34 class G1YoungRemSetSamplingThread; 35 class outputStream; 36 class ThreadClosure; 37 38 class ConcurrentG1Refine: public CHeapObj<mtGC> { 39 G1YoungRemSetSamplingThread* _sample_thread; 40 41 ConcurrentG1RefineThread** _threads; 42 uint _n_worker_threads; 43 /* 44 * The value of the update buffer queue length falls into one of 3 zones: 45 * green, yellow, red. If the value is in [0, green) nothing is 46 * done, the buffers are left unprocessed to enable the caching effect of the 47 * dirtied cards. In the yellow zone [green, yellow) the concurrent refinement 48 * threads are gradually activated. In [yellow, red) all threads are 49 * running. If the length becomes red (max queue length) the mutators start 50 * processing the buffers. 51 * 52 * There are some interesting cases (when G1UseAdaptiveConcRefinement 53 * is turned off): 54 * 1) green = yellow = red = 0. In this case the mutator will process all 55 * buffers. Except for those that are created by the deferred updates 56 * machinery during a collection. 57 * 2) green = 0. Means no caching. Can be a good way to minimize the 58 * amount of time spent updating rsets during a collection. 59 */ 60 size_t _green_zone; 61 size_t _yellow_zone; 62 size_t _red_zone; 63 size_t _min_yellow_zone_size; 64 65 ConcurrentG1Refine(size_t green_zone, 66 size_t yellow_zone, 67 size_t red_zone, 68 size_t min_yellow_zone_size); 69 70 // Update green/yellow/red zone values based on how well goals are being met. 71 void update_zones(double update_rs_time, 72 size_t update_rs_processed_buffers, 73 double goal_ms); 74 75 // Update thread thresholds to account for updated zone values. 76 void update_thread_thresholds(); 77 78 public: 79 ~ConcurrentG1Refine(); 80 81 // Returns ConcurrentG1Refine instance if succeeded to create/initialize ConcurrentG1Refine and ConcurrentG1RefineThread. 82 // Otherwise, returns NULL with error code. 83 static ConcurrentG1Refine* create(jint* ecode); 84 85 void stop(); 86 87 void adjust(double update_rs_time, size_t update_rs_processed_buffers, double goal_ms); 88 89 // Iterate over all concurrent refinement threads 90 void threads_do(ThreadClosure *tc); 91 92 // Iterate over all worker refinement threads 93 void worker_threads_do(ThreadClosure * tc); 94 95 // The RS sampling thread has nothing to do with refinement, but is here for now. 96 G1YoungRemSetSamplingThread * sampling_thread() const { return _sample_thread; } 97 98 static uint thread_num(); 99 100 void print_worker_threads_on(outputStream* st) const; 101 102 size_t green_zone() const { return _green_zone; } 103 size_t yellow_zone() const { return _yellow_zone; } 104 size_t red_zone() const { return _red_zone; } 105 }; 106 107 #endif // SHARE_VM_GC_G1_CONCURRENTG1REFINE_HPP