1 /* 2 * Copyright (c) 2001, 2017, 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_G1CONCURRENTREFINE_HPP 26 #define SHARE_VM_GC_G1_G1CONCURRENTREFINE_HPP 27 28 #include "memory/allocation.hpp" 29 #include "utilities/globalDefinitions.hpp" 30 31 // Forward decl 32 class CardTableEntryClosure; 33 class G1ConcurrentRefineThread; 34 class outputStream; 35 class ThreadClosure; 36 37 class G1ConcurrentRefine : public CHeapObj<mtGC> { 38 G1ConcurrentRefineThread** _threads; 39 uint _n_worker_threads; 40 /* 41 * The value of the update buffer queue length falls into one of 3 zones: 42 * green, yellow, red. If the value is in [0, green) nothing is 43 * done, the buffers are left unprocessed to enable the caching effect of the 44 * dirtied cards. In the yellow zone [green, yellow) the concurrent refinement 45 * threads are gradually activated. In [yellow, red) all threads are 46 * running. If the length becomes red (max queue length) the mutators start 47 * processing the buffers. 48 * 49 * There are some interesting cases (when G1UseAdaptiveConcRefinement 50 * is turned off): 51 * 1) green = yellow = red = 0. In this case the mutator will process all 52 * buffers. Except for those that are created by the deferred updates 53 * machinery during a collection. 54 * 2) green = 0. Means no caching. Can be a good way to minimize the 55 * amount of time spent updating rsets during a collection. 56 */ 57 size_t _green_zone; 58 size_t _yellow_zone; 59 size_t _red_zone; 60 size_t _min_yellow_zone_size; 61 62 G1ConcurrentRefine(size_t green_zone, 63 size_t yellow_zone, 64 size_t red_zone, 65 size_t min_yellow_zone_size); 66 67 // Update green/yellow/red zone values based on how well goals are being met. 68 void update_zones(double update_rs_time, 69 size_t update_rs_processed_buffers, 70 double goal_ms); 71 72 // Update thread thresholds to account for updated zone values. 73 void update_thread_thresholds(); 74 75 public: 76 ~G1ConcurrentRefine(); 77 78 // Returns a G1ConcurrentRefine instance if succeeded to create/initialize G1ConcurrentRefine and G1ConcurrentRefineThreads. 79 // Otherwise, returns NULL with error code. 80 static G1ConcurrentRefine* create(jint* ecode); 81 82 void stop(); 83 84 void adjust(double update_rs_time, size_t update_rs_processed_buffers, double goal_ms); 85 86 // Iterate over all concurrent refinement threads applying the given closure. 87 void threads_do(ThreadClosure *tc); 88 89 static uint thread_num(); 90 91 void print_threads_on(outputStream* st) const; 92 93 size_t green_zone() const { return _green_zone; } 94 size_t yellow_zone() const { return _yellow_zone; } 95 size_t red_zone() const { return _red_zone; } 96 }; 97 98 #endif // SHARE_VM_GC_G1_G1CONCURRENTREFINE_HPP