| /* |
| * Copyright (c) 2001, 2020, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "gc/g1/g1BarrierSet.hpp" |
| #include "gc/g1/g1ConcurrentRefine.hpp" |
| #include "gc/g1/g1ConcurrentRefineThread.hpp" |
| #include "gc/g1/g1DirtyCardQueue.hpp" |
| #include "logging/log.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "memory/iterator.hpp" |
| #include "runtime/globals_extension.hpp" |
| #include "runtime/java.hpp" |
| #include "runtime/thread.hpp" |
| #include "utilities/debug.hpp" |
| #include "utilities/globalDefinitions.hpp" |
| #include "utilities/pair.hpp" |
| #include <math.h> |
| |
| G1ConcurrentRefineThread* G1ConcurrentRefineThreadControl::create_refinement_thread(uint worker_id, bool initializing) { |
| G1ConcurrentRefineThread* result = NULL; |
| if (initializing || !InjectGCWorkerCreationFailure) { |
| result = new G1ConcurrentRefineThread(_cr, worker_id); |
| } |
| if (result == NULL || result->osthread() == NULL) { |
| log_warning(gc)("Failed to create refinement thread %u, no more %s", |
| worker_id, |
| result == NULL ? "memory" : "OS threads"); |
| } |
| return result; |
| } |
| |
| G1ConcurrentRefineThreadControl::G1ConcurrentRefineThreadControl() : |
| _cr(NULL), |
| _threads(NULL), |
| _num_max_threads(0) |
| { |
| } |
| |
| G1ConcurrentRefineThreadControl::~G1ConcurrentRefineThreadControl() { |
| for (uint i = 0; i < _num_max_threads; i++) { |
| G1ConcurrentRefineThread* t = _threads[i]; |
| if (t != NULL) { |
| delete t; |
| } |
| } |
| FREE_C_HEAP_ARRAY(G1ConcurrentRefineThread*, _threads); |
| } |
| |
| jint G1ConcurrentRefineThreadControl::initialize(G1ConcurrentRefine* cr, uint num_max_threads) { |
| assert(cr != NULL, "G1ConcurrentRefine must not be NULL"); |
| _cr = cr; |
| _num_max_threads = num_max_threads; |
| |
| _threads = NEW_C_HEAP_ARRAY(G1ConcurrentRefineThread*, num_max_threads, mtGC); |
| |
| for (uint i = 0; i < num_max_threads; i++) { |
| if (UseDynamicNumberOfGCThreads && i != 0 /* Always start first thread. */) { |
| _threads[i] = NULL; |
| } else { |
| _threads[i] = create_refinement_thread(i, true); |
| if (_threads[i] == NULL) { |
| vm_shutdown_during_initialization("Could not allocate refinement threads."); |
| return JNI_ENOMEM; |
| } |
| } |
| } |
| |
| if (num_max_threads > 0) { |
| G1BarrierSet::dirty_card_queue_set().set_primary_refinement_thread(_threads[0]); |
| } |
| |
| return JNI_OK; |
| } |
| |
| void G1ConcurrentRefineThreadControl::maybe_activate_next(uint cur_worker_id) { |
| assert(cur_worker_id < _num_max_threads, |
| "Activating another thread from %u not allowed since there can be at most %u", |
| cur_worker_id, _num_max_threads); |
| if (cur_worker_id == (_num_max_threads - 1)) { |
| // Already the last thread, there is no more thread to activate. |
| return; |
| } |
| |
| uint worker_id = cur_worker_id + 1; |
| G1ConcurrentRefineThread* thread_to_activate = _threads[worker_id]; |
| if (thread_to_activate == NULL) { |
| // Still need to create the thread... |
| _threads[worker_id] = create_refinement_thread(worker_id, false); |
| thread_to_activate = _threads[worker_id]; |
| } |
| if (thread_to_activate != NULL) { |
| thread_to_activate->activate(); |
| } |
| } |
| |
| void G1ConcurrentRefineThreadControl::worker_threads_do(ThreadClosure* tc) { |
| for (uint i = 0; i < _num_max_threads; i++) { |
| if (_threads[i] != NULL) { |
| tc->do_thread(_threads[i]); |
| } |
| } |
| } |
| |
| void G1ConcurrentRefineThreadControl::stop() { |
| for (uint i = 0; i < _num_max_threads; i++) { |
| if (_threads[i] != NULL) { |
| _threads[i]->stop(); |
| } |
| } |
| } |
| |
| // Arbitrary but large limits, to simplify some of the zone calculations. |
| // The general idea is to allow expressions like |
| // MIN2(x OP y, max_XXX_zone) |
| // without needing to check for overflow in "x OP y", because the |
| // ranges for x and y have been restricted. |
| STATIC_ASSERT(sizeof(LP64_ONLY(jint) NOT_LP64(jshort)) <= (sizeof(size_t)/2)); |
| const size_t max_yellow_zone = LP64_ONLY(max_jint) NOT_LP64(max_jshort); |
| const size_t max_green_zone = max_yellow_zone / 2; |
| const size_t max_red_zone = INT_MAX; // For dcqs.set_max_cards. |
| STATIC_ASSERT(max_yellow_zone <= max_red_zone); |
| |
| // Range check assertions for green zone values. |
| #define assert_zone_constraints_g(green) \ |
| do { \ |
| size_t azc_g_green = (green); \ |
| assert(azc_g_green <= max_green_zone, \ |
| "green exceeds max: " SIZE_FORMAT, azc_g_green); \ |
| } while (0) |
| |
| // Range check assertions for green and yellow zone values. |
| #define assert_zone_constraints_gy(green, yellow) \ |
| do { \ |
| size_t azc_gy_green = (green); \ |
| size_t azc_gy_yellow = (yellow); \ |
| assert_zone_constraints_g(azc_gy_green); \ |
| assert(azc_gy_yellow <= max_yellow_zone, \ |
| "yellow exceeds max: " SIZE_FORMAT, azc_gy_yellow); \ |
| assert(azc_gy_green <= azc_gy_yellow, \ |
| "green (" SIZE_FORMAT ") exceeds yellow (" SIZE_FORMAT ")", \ |
| azc_gy_green, azc_gy_yellow); \ |
| } while (0) |
| |
| // Range check assertions for green, yellow, and red zone values. |
| #define assert_zone_constraints_gyr(green, yellow, red) \ |
| do { \ |
| size_t azc_gyr_green = (green); \ |
| size_t azc_gyr_yellow = (yellow); \ |
| size_t azc_gyr_red = (red); \ |
| assert_zone_constraints_gy(azc_gyr_green, azc_gyr_yellow); \ |
| assert(azc_gyr_red <= max_red_zone, \ |
| "red exceeds max: " SIZE_FORMAT, azc_gyr_red); \ |
| assert(azc_gyr_yellow <= azc_gyr_red, \ |
| "yellow (" SIZE_FORMAT ") exceeds red (" SIZE_FORMAT ")", \ |
| azc_gyr_yellow, azc_gyr_red); \ |
| } while (0) |
| |
| // Logging tag sequence for refinement control updates. |
| #define CTRL_TAGS gc, ergo, refine |
| |
| // For logging zone values, ensuring consistency of level and tags. |
| #define LOG_ZONES(...) log_debug( CTRL_TAGS )(__VA_ARGS__) |
| |
| static size_t buffers_to_cards(size_t value) { |
| return value * G1UpdateBufferSize; |
| } |
| |
| // Package for pair of refinement thread activation and deactivation |
| // thresholds. The activation and deactivation levels are resp. the first |
| // and second values of the pair. |
| typedef Pair<size_t, size_t> Thresholds; |
| inline size_t activation_level(const Thresholds& t) { return t.first; } |
| inline size_t deactivation_level(const Thresholds& t) { return t.second; } |
| |
| static Thresholds calc_thresholds(size_t green_zone, |
| size_t yellow_zone, |
| uint worker_id) { |
| double yellow_size = yellow_zone - green_zone; |
| double step = yellow_size / G1ConcurrentRefine::max_num_threads(); |
| if (worker_id == 0) { |
| // Potentially activate worker 0 more aggressively, to keep |
| // available buffers near green_zone value. When yellow_size is |
| // large we don't want to allow a full step to accumulate before |
| // doing any processing, as that might lead to significantly more |
| // than green_zone buffers to be processed during pause. So limit |
| // to an extra half buffer per pause-time processing thread. |
| step = MIN2(step, buffers_to_cards(ParallelGCThreads) / 2.0); |
| } |
| size_t activate_offset = static_cast<size_t>(ceil(step * (worker_id + 1))); |
| size_t deactivate_offset = static_cast<size_t>(floor(step * worker_id)); |
| return Thresholds(green_zone + activate_offset, |
| green_zone + deactivate_offset); |
| } |
| |
| G1ConcurrentRefine::G1ConcurrentRefine(size_t green_zone, |
| size_t yellow_zone, |
| size_t red_zone, |
| size_t min_yellow_zone_size) : |
| _thread_control(), |
| _green_zone(green_zone), |
| _yellow_zone(yellow_zone), |
| _red_zone(red_zone), |
| _min_yellow_zone_size(min_yellow_zone_size) |
| { |
| assert_zone_constraints_gyr(green_zone, yellow_zone, red_zone); |
| } |
| |
| jint G1ConcurrentRefine::initialize() { |
| return _thread_control.initialize(this, max_num_threads()); |
| } |
| |
| static size_t calc_min_yellow_zone_size() { |
| size_t step = buffers_to_cards(G1ConcRefinementThresholdStep); |
| uint n_workers = G1ConcurrentRefine::max_num_threads(); |
| if ((max_yellow_zone / step) < n_workers) { |
| return max_yellow_zone; |
| } else { |
| return step * n_workers; |
| } |
| } |
| |
| static size_t calc_init_green_zone() { |
| size_t green = G1ConcRefinementGreenZone; |
| if (FLAG_IS_DEFAULT(G1ConcRefinementGreenZone)) { |
| green = ParallelGCThreads; |
| } |
| green = buffers_to_cards(green); |
| return MIN2(green, max_green_zone); |
| } |
| |
| static size_t calc_init_yellow_zone(size_t green, size_t min_size) { |
| size_t config = buffers_to_cards(G1ConcRefinementYellowZone); |
| size_t size = 0; |
| if (FLAG_IS_DEFAULT(G1ConcRefinementYellowZone)) { |
| size = green * 2; |
| } else if (green < config) { |
| size = config - green; |
| } |
| size = MAX2(size, min_size); |
| size = MIN2(size, max_yellow_zone); |
| return MIN2(green + size, max_yellow_zone); |
| } |
| |
| static size_t calc_init_red_zone(size_t green, size_t yellow) { |
| size_t size = yellow - green; |
| if (!FLAG_IS_DEFAULT(G1ConcRefinementRedZone)) { |
| size_t config = buffers_to_cards(G1ConcRefinementRedZone); |
| if (yellow < config) { |
| size = MAX2(size, config - yellow); |
| } |
| } |
| return MIN2(yellow + size, max_red_zone); |
| } |
| |
| G1ConcurrentRefine* G1ConcurrentRefine::create(jint* ecode) { |
| size_t min_yellow_zone_size = calc_min_yellow_zone_size(); |
| size_t green_zone = calc_init_green_zone(); |
| size_t yellow_zone = calc_init_yellow_zone(green_zone, min_yellow_zone_size); |
| size_t red_zone = calc_init_red_zone(green_zone, yellow_zone); |
| |
| LOG_ZONES("Initial Refinement Zones: " |
| "green: " SIZE_FORMAT ", " |
| "yellow: " SIZE_FORMAT ", " |
| "red: " SIZE_FORMAT ", " |
| "min yellow size: " SIZE_FORMAT, |
| green_zone, yellow_zone, red_zone, min_yellow_zone_size); |
| |
| G1ConcurrentRefine* cr = new G1ConcurrentRefine(green_zone, |
| yellow_zone, |
| red_zone, |
| min_yellow_zone_size); |
| *ecode = cr->initialize(); |
| return cr; |
| } |
| |
| void G1ConcurrentRefine::stop() { |
| _thread_control.stop(); |
| } |
| |
| G1ConcurrentRefine::~G1ConcurrentRefine() { |
| } |
| |
| void G1ConcurrentRefine::threads_do(ThreadClosure *tc) { |
| _thread_control.worker_threads_do(tc); |
| } |
| |
| uint G1ConcurrentRefine::max_num_threads() { |
| return G1ConcRefinementThreads; |
| } |
| |
| static size_t calc_new_green_zone(size_t green, |
| double logged_cards_scan_time, |
| size_t processed_logged_cards, |
| double goal_ms) { |
| // Adjust green zone based on whether we're meeting the time goal. |
| // Limit to max_green_zone. |
| const double inc_k = 1.1, dec_k = 0.9; |
| if (logged_cards_scan_time > goal_ms) { |
| if (green > 0) { |
| green = static_cast<size_t>(green * dec_k); |
| } |
| } else if (logged_cards_scan_time < goal_ms && |
| processed_logged_cards > green) { |
| green = static_cast<size_t>(MAX2(green * inc_k, green + 1.0)); |
| green = MIN2(green, max_green_zone); |
| } |
| return green; |
| } |
| |
| static size_t calc_new_yellow_zone(size_t green, size_t min_yellow_size) { |
| size_t size = green * 2; |
| size = MAX2(size, min_yellow_size); |
| return MIN2(green + size, max_yellow_zone); |
| } |
| |
| static size_t calc_new_red_zone(size_t green, size_t yellow) { |
| return MIN2(yellow + (yellow - green), max_red_zone); |
| } |
| |
| void G1ConcurrentRefine::update_zones(double logged_cards_scan_time, |
| size_t processed_logged_cards, |
| double goal_ms) { |
| log_trace( CTRL_TAGS )("Updating Refinement Zones: " |
| "logged cards scan time: %.3fms, " |
| "processed cards: " SIZE_FORMAT ", " |
| "goal time: %.3fms", |
| logged_cards_scan_time, |
| processed_logged_cards, |
| goal_ms); |
| |
| _green_zone = calc_new_green_zone(_green_zone, |
| logged_cards_scan_time, |
| processed_logged_cards, |
| goal_ms); |
| _yellow_zone = calc_new_yellow_zone(_green_zone, _min_yellow_zone_size); |
| _red_zone = calc_new_red_zone(_green_zone, _yellow_zone); |
| |
| assert_zone_constraints_gyr(_green_zone, _yellow_zone, _red_zone); |
| LOG_ZONES("Updated Refinement Zones: " |
| "green: " SIZE_FORMAT ", " |
| "yellow: " SIZE_FORMAT ", " |
| "red: " SIZE_FORMAT, |
| _green_zone, _yellow_zone, _red_zone); |
| } |
| |
| void G1ConcurrentRefine::adjust(double logged_cards_scan_time, |
| size_t processed_logged_cards, |
| double goal_ms) { |
| G1DirtyCardQueueSet& dcqs = G1BarrierSet::dirty_card_queue_set(); |
| |
| if (G1UseAdaptiveConcRefinement) { |
| update_zones(logged_cards_scan_time, processed_logged_cards, goal_ms); |
| |
| // Change the barrier params |
| if (max_num_threads() == 0) { |
| // Disable dcqs notification when there are no threads to notify. |
| dcqs.set_process_cards_threshold(G1DirtyCardQueueSet::ProcessCardsThresholdNever); |
| } else { |
| // Worker 0 is the primary; wakeup is via dcqs notification. |
| STATIC_ASSERT(max_yellow_zone <= INT_MAX); |
| size_t activate = activation_threshold(0); |
| dcqs.set_process_cards_threshold(activate); |
| } |
| dcqs.set_max_cards(red_zone()); |
| } |
| |
| size_t curr_queue_size = dcqs.num_cards(); |
| if ((dcqs.max_cards() > 0) && |
| (curr_queue_size >= yellow_zone())) { |
| dcqs.set_max_cards_padding(curr_queue_size); |
| } else { |
| dcqs.set_max_cards_padding(0); |
| } |
| dcqs.notify_if_necessary(); |
| } |
| |
| G1ConcurrentRefineStats G1ConcurrentRefine::get_and_reset_refinement_stats() { |
| struct CollectStats : public ThreadClosure { |
| G1ConcurrentRefineStats _total_stats; |
| virtual void do_thread(Thread* t) { |
| G1ConcurrentRefineThread* crt = static_cast<G1ConcurrentRefineThread*>(t); |
| G1ConcurrentRefineStats& stats = *crt->refinement_stats(); |
| _total_stats += stats; |
| stats.reset(); |
| } |
| } collector; |
| threads_do(&collector); |
| return collector._total_stats; |
| } |
| |
| size_t G1ConcurrentRefine::activation_threshold(uint worker_id) const { |
| Thresholds thresholds = calc_thresholds(_green_zone, _yellow_zone, worker_id); |
| return activation_level(thresholds); |
| } |
| |
| size_t G1ConcurrentRefine::deactivation_threshold(uint worker_id) const { |
| Thresholds thresholds = calc_thresholds(_green_zone, _yellow_zone, worker_id); |
| return deactivation_level(thresholds); |
| } |
| |
| uint G1ConcurrentRefine::worker_id_offset() { |
| return G1DirtyCardQueueSet::num_par_ids(); |
| } |
| |
| void G1ConcurrentRefine::maybe_activate_more_threads(uint worker_id, size_t num_cur_cards) { |
| if (num_cur_cards > activation_threshold(worker_id + 1)) { |
| _thread_control.maybe_activate_next(worker_id); |
| } |
| } |
| |
| bool G1ConcurrentRefine::do_refinement_step(uint worker_id, |
| G1ConcurrentRefineStats* stats) { |
| G1DirtyCardQueueSet& dcqs = G1BarrierSet::dirty_card_queue_set(); |
| |
| size_t curr_cards = dcqs.num_cards(); |
| // If the number of the cards falls down into the yellow zone, |
| // that means that the transition period after the evacuation pause has ended. |
| if (curr_cards <= yellow_zone()) { |
| dcqs.discard_max_cards_padding(); |
| } |
| |
| maybe_activate_more_threads(worker_id, curr_cards); |
| |
| // Process the next buffer, if there are enough left. |
| return dcqs.refine_completed_buffer_concurrently(worker_id + worker_id_offset(), |
| deactivation_threshold(worker_id), |
| stats); |
| } |