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 #include "precompiled.hpp" 26 #include "gc/g1/g1ConcurrentRefine.hpp" 27 #include "gc/g1/g1ConcurrentRefineThread.hpp" 28 #include "gc/g1/g1YoungRemSetSamplingThread.hpp" 29 #include "logging/log.hpp" 30 #include "runtime/java.hpp" 31 #include "runtime/thread.hpp" 32 #include "utilities/debug.hpp" 33 #include "utilities/globalDefinitions.hpp" 34 #include "utilities/pair.hpp" 35 #include <math.h> 36 37 // Arbitrary but large limits, to simplify some of the zone calculations. 38 // The general idea is to allow expressions like 39 // MIN2(x OP y, max_XXX_zone) 40 // without needing to check for overflow in "x OP y", because the 41 // ranges for x and y have been restricted. 42 STATIC_ASSERT(sizeof(LP64_ONLY(jint) NOT_LP64(jshort)) <= (sizeof(size_t)/2)); 43 const size_t max_yellow_zone = LP64_ONLY(max_jint) NOT_LP64(max_jshort); 44 const size_t max_green_zone = max_yellow_zone / 2; 45 const size_t max_red_zone = INT_MAX; // For dcqs.set_max_completed_queue. 46 STATIC_ASSERT(max_yellow_zone <= max_red_zone); 47 48 // Range check assertions for green zone values. 49 #define assert_zone_constraints_g(green) \ 50 do { \ 51 size_t azc_g_green = (green); \ 52 assert(azc_g_green <= max_green_zone, \ 53 "green exceeds max: " SIZE_FORMAT, azc_g_green); \ 54 } while (0) 55 56 // Range check assertions for green and yellow zone values. 57 #define assert_zone_constraints_gy(green, yellow) \ 58 do { \ 59 size_t azc_gy_green = (green); \ 60 size_t azc_gy_yellow = (yellow); \ 61 assert_zone_constraints_g(azc_gy_green); \ 62 assert(azc_gy_yellow <= max_yellow_zone, \ 63 "yellow exceeds max: " SIZE_FORMAT, azc_gy_yellow); \ 64 assert(azc_gy_green <= azc_gy_yellow, \ 65 "green (" SIZE_FORMAT ") exceeds yellow (" SIZE_FORMAT ")", \ 66 azc_gy_green, azc_gy_yellow); \ 67 } while (0) 68 69 // Range check assertions for green, yellow, and red zone values. 70 #define assert_zone_constraints_gyr(green, yellow, red) \ 71 do { \ 72 size_t azc_gyr_green = (green); \ 73 size_t azc_gyr_yellow = (yellow); \ 74 size_t azc_gyr_red = (red); \ 75 assert_zone_constraints_gy(azc_gyr_green, azc_gyr_yellow); \ 76 assert(azc_gyr_red <= max_red_zone, \ 77 "red exceeds max: " SIZE_FORMAT, azc_gyr_red); \ 78 assert(azc_gyr_yellow <= azc_gyr_red, \ 79 "yellow (" SIZE_FORMAT ") exceeds red (" SIZE_FORMAT ")", \ 80 azc_gyr_yellow, azc_gyr_red); \ 81 } while (0) 82 83 // Logging tag sequence for refinement control updates. 84 #define CTRL_TAGS gc, ergo, refine 85 86 // For logging zone values, ensuring consistency of level and tags. 87 #define LOG_ZONES(...) log_debug( CTRL_TAGS )(__VA_ARGS__) 88 89 // Package for pair of refinement thread activation and deactivation 90 // thresholds. The activation and deactivation levels are resp. the first 91 // and second values of the pair. 92 typedef Pair<size_t, size_t> Thresholds; 93 inline size_t activation_level(const Thresholds& t) { return t.first; } 94 inline size_t deactivation_level(const Thresholds& t) { return t.second; } 95 96 static Thresholds calc_thresholds(size_t green_zone, 97 size_t yellow_zone, 98 uint worker_i) { 99 double yellow_size = yellow_zone - green_zone; 100 double step = yellow_size / G1ConcurrentRefine::thread_num(); 101 if (worker_i == 0) { 102 // Potentially activate worker 0 more aggressively, to keep 103 // available buffers near green_zone value. When yellow_size is 104 // large we don't want to allow a full step to accumulate before 105 // doing any processing, as that might lead to significantly more 106 // than green_zone buffers to be processed by update_rs. 107 step = MIN2(step, ParallelGCThreads / 2.0); 108 } 109 size_t activate_offset = static_cast<size_t>(ceil(step * (worker_i + 1))); 110 size_t deactivate_offset = static_cast<size_t>(floor(step * worker_i)); 111 return Thresholds(green_zone + activate_offset, 112 green_zone + deactivate_offset); 113 } 114 115 G1ConcurrentRefine::G1ConcurrentRefine(size_t green_zone, 116 size_t yellow_zone, 117 size_t red_zone, 118 size_t min_yellow_zone_size) : 119 _threads(NULL), 120 _sample_thread(NULL), 121 _n_worker_threads(thread_num()), 122 _green_zone(green_zone), 123 _yellow_zone(yellow_zone), 124 _red_zone(red_zone), 125 _min_yellow_zone_size(min_yellow_zone_size) 126 { 127 assert_zone_constraints_gyr(green_zone, yellow_zone, red_zone); 128 } 129 130 static size_t calc_min_yellow_zone_size() { 131 size_t step = G1ConcRefinementThresholdStep; 132 uint n_workers = G1ConcurrentRefine::thread_num(); 133 if ((max_yellow_zone / step) < n_workers) { 134 return max_yellow_zone; 135 } else { 136 return step * n_workers; 137 } 138 } 139 140 static size_t calc_init_green_zone() { 141 size_t green = G1ConcRefinementGreenZone; 142 if (FLAG_IS_DEFAULT(G1ConcRefinementGreenZone)) { 143 green = ParallelGCThreads; 144 } 145 return MIN2(green, max_green_zone); 146 } 147 148 static size_t calc_init_yellow_zone(size_t green, size_t min_size) { 149 size_t config = G1ConcRefinementYellowZone; 150 size_t size = 0; 151 if (FLAG_IS_DEFAULT(G1ConcRefinementYellowZone)) { 152 size = green * 2; 153 } else if (green < config) { 154 size = config - green; 155 } 156 size = MAX2(size, min_size); 157 size = MIN2(size, max_yellow_zone); 158 return MIN2(green + size, max_yellow_zone); 159 } 160 161 static size_t calc_init_red_zone(size_t green, size_t yellow) { 162 size_t size = yellow - green; 163 if (!FLAG_IS_DEFAULT(G1ConcRefinementRedZone)) { 164 size_t config = G1ConcRefinementRedZone; 165 if (yellow < config) { 166 size = MAX2(size, config - yellow); 167 } 168 } 169 return MIN2(yellow + size, max_red_zone); 170 } 171 172 G1ConcurrentRefine* G1ConcurrentRefine::create(jint* ecode) { 173 size_t min_yellow_zone_size = calc_min_yellow_zone_size(); 174 size_t green_zone = calc_init_green_zone(); 175 size_t yellow_zone = calc_init_yellow_zone(green_zone, min_yellow_zone_size); 176 size_t red_zone = calc_init_red_zone(green_zone, yellow_zone); 177 178 LOG_ZONES("Initial Refinement Zones: " 179 "green: " SIZE_FORMAT ", " 180 "yellow: " SIZE_FORMAT ", " 181 "red: " SIZE_FORMAT ", " 182 "min yellow size: " SIZE_FORMAT, 183 green_zone, yellow_zone, red_zone, min_yellow_zone_size); 184 185 G1ConcurrentRefine* cg1r = new G1ConcurrentRefine(green_zone, 186 yellow_zone, 187 red_zone, 188 min_yellow_zone_size); 189 190 if (cg1r == NULL) { 191 *ecode = JNI_ENOMEM; 192 vm_shutdown_during_initialization("Could not create G1ConcurrentRefine"); 193 return NULL; 194 } 195 196 cg1r->_threads = NEW_C_HEAP_ARRAY_RETURN_NULL(G1ConcurrentRefineThread*, cg1r->_n_worker_threads, mtGC); 197 if (cg1r->_threads == NULL) { 198 *ecode = JNI_ENOMEM; 199 vm_shutdown_during_initialization("Could not allocate an array for G1ConcurrentRefineThread"); 200 return NULL; 201 } 202 203 uint worker_id_offset = DirtyCardQueueSet::num_par_ids(); 204 205 G1ConcurrentRefineThread *next = NULL; 206 for (uint i = cg1r->_n_worker_threads - 1; i != UINT_MAX; i--) { 207 Thresholds thresholds = calc_thresholds(green_zone, yellow_zone, i); 208 G1ConcurrentRefineThread* t = 209 new G1ConcurrentRefineThread(cg1r, 210 next, 211 worker_id_offset, 212 i, 213 activation_level(thresholds), 214 deactivation_level(thresholds)); 215 assert(t != NULL, "Conc refine should have been created"); 216 if (t->osthread() == NULL) { 217 *ecode = JNI_ENOMEM; 218 vm_shutdown_during_initialization("Could not create G1ConcurrentRefineThread"); 219 return NULL; 220 } 221 222 assert(t->cg1r() == cg1r, "Conc refine thread should refer to this"); 223 cg1r->_threads[i] = t; 224 next = t; 225 } 226 227 cg1r->_sample_thread = new G1YoungRemSetSamplingThread(); 228 if (cg1r->_sample_thread->osthread() == NULL) { 229 *ecode = JNI_ENOMEM; 230 vm_shutdown_during_initialization("Could not create G1YoungRemSetSamplingThread"); 231 return NULL; 232 } 233 234 *ecode = JNI_OK; 235 return cg1r; 236 } 237 238 void G1ConcurrentRefine::stop() { 239 for (uint i = 0; i < _n_worker_threads; i++) { 240 _threads[i]->stop(); 241 } 242 _sample_thread->stop(); 243 } 244 245 void G1ConcurrentRefine::update_thread_thresholds() { 246 for (uint i = 0; i < _n_worker_threads; i++) { 247 Thresholds thresholds = calc_thresholds(_green_zone, _yellow_zone, i); 248 _threads[i]->update_thresholds(activation_level(thresholds), 249 deactivation_level(thresholds)); 250 } 251 } 252 253 G1ConcurrentRefine::~G1ConcurrentRefine() { 254 for (uint i = 0; i < _n_worker_threads; i++) { 255 delete _threads[i]; 256 } 257 FREE_C_HEAP_ARRAY(G1ConcurrentRefineThread*, _threads); 258 259 delete _sample_thread; 260 } 261 262 void G1ConcurrentRefine::threads_do(ThreadClosure *tc) { 263 worker_threads_do(tc); 264 tc->do_thread(_sample_thread); 265 } 266 267 void G1ConcurrentRefine::worker_threads_do(ThreadClosure * tc) { 268 for (uint i = 0; i < _n_worker_threads; i++) { 269 tc->do_thread(_threads[i]); 270 } 271 } 272 273 uint G1ConcurrentRefine::thread_num() { 274 return G1ConcRefinementThreads; 275 } 276 277 void G1ConcurrentRefine::print_worker_threads_on(outputStream* st) const { 278 for (uint i = 0; i < _n_worker_threads; ++i) { 279 _threads[i]->print_on(st); 280 st->cr(); 281 } 282 _sample_thread->print_on(st); 283 st->cr(); 284 } 285 286 static size_t calc_new_green_zone(size_t green, 287 double update_rs_time, 288 size_t update_rs_processed_buffers, 289 double goal_ms) { 290 // Adjust green zone based on whether we're meeting the time goal. 291 // Limit to max_green_zone. 292 const double inc_k = 1.1, dec_k = 0.9; 293 if (update_rs_time > goal_ms) { 294 if (green > 0) { 295 green = static_cast<size_t>(green * dec_k); 296 } 297 } else if (update_rs_time < goal_ms && 298 update_rs_processed_buffers > green) { 299 green = static_cast<size_t>(MAX2(green * inc_k, green + 1.0)); 300 green = MIN2(green, max_green_zone); 301 } 302 return green; 303 } 304 305 static size_t calc_new_yellow_zone(size_t green, size_t min_yellow_size) { 306 size_t size = green * 2; 307 size = MAX2(size, min_yellow_size); 308 return MIN2(green + size, max_yellow_zone); 309 } 310 311 static size_t calc_new_red_zone(size_t green, size_t yellow) { 312 return MIN2(yellow + (yellow - green), max_red_zone); 313 } 314 315 void G1ConcurrentRefine::update_zones(double update_rs_time, 316 size_t update_rs_processed_buffers, 317 double goal_ms) { 318 log_trace( CTRL_TAGS )("Updating Refinement Zones: " 319 "update_rs time: %.3fms, " 320 "update_rs buffers: " SIZE_FORMAT ", " 321 "update_rs goal time: %.3fms", 322 update_rs_time, 323 update_rs_processed_buffers, 324 goal_ms); 325 326 _green_zone = calc_new_green_zone(_green_zone, 327 update_rs_time, 328 update_rs_processed_buffers, 329 goal_ms); 330 _yellow_zone = calc_new_yellow_zone(_green_zone, _min_yellow_zone_size); 331 _red_zone = calc_new_red_zone(_green_zone, _yellow_zone); 332 333 assert_zone_constraints_gyr(_green_zone, _yellow_zone, _red_zone); 334 LOG_ZONES("Updated Refinement Zones: " 335 "green: " SIZE_FORMAT ", " 336 "yellow: " SIZE_FORMAT ", " 337 "red: " SIZE_FORMAT, 338 _green_zone, _yellow_zone, _red_zone); 339 } 340 341 void G1ConcurrentRefine::adjust(double update_rs_time, 342 size_t update_rs_processed_buffers, 343 double goal_ms) { 344 DirtyCardQueueSet& dcqs = JavaThread::dirty_card_queue_set(); 345 346 if (G1UseAdaptiveConcRefinement) { 347 update_zones(update_rs_time, update_rs_processed_buffers, goal_ms); 348 update_thread_thresholds(); 349 350 // Change the barrier params 351 if (_n_worker_threads == 0) { 352 // Disable dcqs notification when there are no threads to notify. 353 dcqs.set_process_completed_threshold(INT_MAX); 354 } else { 355 // Worker 0 is the primary; wakeup is via dcqs notification. 356 STATIC_ASSERT(max_yellow_zone <= INT_MAX); 357 size_t activate = _threads[0]->activation_threshold(); 358 dcqs.set_process_completed_threshold((int)activate); 359 } 360 dcqs.set_max_completed_queue((int)red_zone()); 361 } 362 363 size_t curr_queue_size = dcqs.completed_buffers_num(); 364 if (curr_queue_size >= yellow_zone()) { 365 dcqs.set_completed_queue_padding(curr_queue_size); 366 } else { 367 dcqs.set_completed_queue_padding(0); 368 } 369 dcqs.notify_if_necessary(); 370 }