1 /* |
1 /* |
2 * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved. |
2 * Copyright (c) 2015, 2019, Oracle and/or its affiliates. All rights reserved. |
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
4 * |
4 * |
5 * This code is free software; you can redistribute it and/or modify it |
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 |
6 * under the terms of the GNU General Public License version 2 only, as |
7 * published by the Free Software Foundation. |
7 * published by the Free Software Foundation. |
64 |
64 |
65 // Perform GC if timer has expired. |
65 // Perform GC if timer has expired. |
66 const double time_since_last_gc = ZStatCycle::time_since_last(); |
66 const double time_since_last_gc = ZStatCycle::time_since_last(); |
67 const double time_until_gc = ZCollectionInterval - time_since_last_gc; |
67 const double time_until_gc = ZCollectionInterval - time_since_last_gc; |
68 |
68 |
69 log_debug(gc, director)("Rule: Timer, Interval: %us, TimeUntilGC: %.3lfs", |
69 log_debug(gc, director)("Rule: Timer, Interval: %us, TimeUntilGC: %.3fs", |
70 ZCollectionInterval, time_until_gc); |
70 ZCollectionInterval, time_until_gc); |
71 |
71 |
72 return time_until_gc <= 0; |
72 return time_until_gc <= 0; |
73 } |
73 } |
74 |
74 |
79 } |
79 } |
80 |
80 |
81 // Perform GC if heap usage passes 10/20/30% and no other GC has been |
81 // Perform GC if heap usage passes 10/20/30% and no other GC has been |
82 // performed yet. This allows us to get some early samples of the GC |
82 // performed yet. This allows us to get some early samples of the GC |
83 // duration, which is needed by the other rules. |
83 // duration, which is needed by the other rules. |
84 const size_t max_capacity = ZHeap::heap()->current_max_capacity(); |
84 const size_t max_capacity = ZHeap::heap()->soft_max_capacity(); |
85 const size_t used = ZHeap::heap()->used(); |
85 const size_t used = ZHeap::heap()->used(); |
86 const double used_threshold_percent = (ZStatCycle::ncycles() + 1) * 0.1; |
86 const double used_threshold_percent = (ZStatCycle::ncycles() + 1) * 0.1; |
87 const size_t used_threshold = max_capacity * used_threshold_percent; |
87 const size_t used_threshold = max_capacity * used_threshold_percent; |
88 |
88 |
89 log_debug(gc, director)("Rule: Warmup %.0f%%, Used: " SIZE_FORMAT "MB, UsedThreshold: " SIZE_FORMAT "MB", |
89 log_debug(gc, director)("Rule: Warmup %.0f%%, Used: " SIZE_FORMAT "MB, UsedThreshold: " SIZE_FORMAT "MB", |
105 // allocation spikes. |
105 // allocation spikes. |
106 |
106 |
107 // Calculate amount of free memory available to Java threads. Note that |
107 // Calculate amount of free memory available to Java threads. Note that |
108 // the heap reserve is not available to Java threads and is therefore not |
108 // the heap reserve is not available to Java threads and is therefore not |
109 // considered part of the free memory. |
109 // considered part of the free memory. |
110 const size_t max_capacity = ZHeap::heap()->current_max_capacity(); |
110 const size_t max_capacity = ZHeap::heap()->soft_max_capacity(); |
111 const size_t max_reserve = ZHeap::heap()->max_reserve(); |
111 const size_t max_reserve = ZHeap::heap()->max_reserve(); |
112 const size_t used = ZHeap::heap()->used(); |
112 const size_t used = ZHeap::heap()->used(); |
113 const size_t free_with_reserve = max_capacity - used; |
113 const size_t free_with_reserve = max_capacity - MIN2(max_capacity, used); |
114 const size_t free = free_with_reserve - MIN2(free_with_reserve, max_reserve); |
114 const size_t free = free_with_reserve - MIN2(free_with_reserve, max_reserve); |
115 |
115 |
116 // Calculate time until OOM given the max allocation rate and the amount |
116 // Calculate time until OOM given the max allocation rate and the amount |
117 // of free memory. The allocation rate is a moving average and we multiply |
117 // of free memory. The allocation rate is a moving average and we multiply |
118 // that with an allocation spike tolerance factor to guard against unforeseen |
118 // that with an allocation spike tolerance factor to guard against unforeseen |
131 // We also deduct the sample interval, so that we don't overshoot the target |
131 // We also deduct the sample interval, so that we don't overshoot the target |
132 // time and end up starting the GC too late in the next interval. |
132 // time and end up starting the GC too late in the next interval. |
133 const double sample_interval = 1.0 / ZStatAllocRate::sample_hz; |
133 const double sample_interval = 1.0 / ZStatAllocRate::sample_hz; |
134 const double time_until_gc = time_until_oom - max_duration_of_gc - sample_interval; |
134 const double time_until_gc = time_until_oom - max_duration_of_gc - sample_interval; |
135 |
135 |
136 log_debug(gc, director)("Rule: Allocation Rate, MaxAllocRate: %.3lfMB/s, Free: " SIZE_FORMAT "MB, MaxDurationOfGC: %.3lfs, TimeUntilGC: %.3lfs", |
136 log_debug(gc, director)("Rule: Allocation Rate, MaxAllocRate: %.3fMB/s, Free: " SIZE_FORMAT "MB, MaxDurationOfGC: %.3fs, TimeUntilGC: %.3fs", |
137 max_alloc_rate / M, free / M, max_duration_of_gc, time_until_gc); |
137 max_alloc_rate / M, free / M, max_duration_of_gc, time_until_gc); |
138 |
138 |
139 return time_until_gc <= 0; |
139 return time_until_gc <= 0; |
140 } |
140 } |
141 |
141 |
153 // Only consider doing a proactive GC if the heap usage has grown by at least |
153 // Only consider doing a proactive GC if the heap usage has grown by at least |
154 // 10% of the max capacity since the previous GC, or more than 5 minutes has |
154 // 10% of the max capacity since the previous GC, or more than 5 minutes has |
155 // passed since the previous GC. This helps avoid superfluous GCs when running |
155 // passed since the previous GC. This helps avoid superfluous GCs when running |
156 // applications with very low allocation rate. |
156 // applications with very low allocation rate. |
157 const size_t used_after_last_gc = ZStatHeap::used_at_relocate_end(); |
157 const size_t used_after_last_gc = ZStatHeap::used_at_relocate_end(); |
158 const size_t used_increase_threshold = ZHeap::heap()->current_max_capacity() * 0.10; // 10% |
158 const size_t used_increase_threshold = ZHeap::heap()->soft_max_capacity() * 0.10; // 10% |
159 const size_t used_threshold = used_after_last_gc + used_increase_threshold; |
159 const size_t used_threshold = used_after_last_gc + used_increase_threshold; |
160 const size_t used = ZHeap::heap()->used(); |
160 const size_t used = ZHeap::heap()->used(); |
161 const double time_since_last_gc = ZStatCycle::time_since_last(); |
161 const double time_since_last_gc = ZStatCycle::time_since_last(); |
162 const double time_since_last_gc_threshold = 5 * 60; // 5 minutes |
162 const double time_since_last_gc_threshold = 5 * 60; // 5 minutes |
163 if (used < used_threshold && time_since_last_gc < time_since_last_gc_threshold) { |
163 if (used < used_threshold && time_since_last_gc < time_since_last_gc_threshold) { |
164 // Don't even consider doing a proactive GC |
164 // Don't even consider doing a proactive GC |
165 log_debug(gc, director)("Rule: Proactive, UsedUntilEnabled: " SIZE_FORMAT "MB, TimeUntilEnabled: %.3lfs", |
165 log_debug(gc, director)("Rule: Proactive, UsedUntilEnabled: " SIZE_FORMAT "MB, TimeUntilEnabled: %.3fs", |
166 (used_threshold - used) / M, |
166 (used_threshold - used) / M, |
167 time_since_last_gc_threshold - time_since_last_gc); |
167 time_since_last_gc_threshold - time_since_last_gc); |
168 return false; |
168 return false; |
169 } |
169 } |
170 |
170 |
173 const AbsSeq& duration_of_gc = ZStatCycle::normalized_duration(); |
173 const AbsSeq& duration_of_gc = ZStatCycle::normalized_duration(); |
174 const double max_duration_of_gc = duration_of_gc.davg() + (duration_of_gc.dsd() * one_in_1000); |
174 const double max_duration_of_gc = duration_of_gc.davg() + (duration_of_gc.dsd() * one_in_1000); |
175 const double acceptable_gc_interval = max_duration_of_gc * ((assumed_throughput_drop_during_gc / acceptable_throughput_drop) - 1.0); |
175 const double acceptable_gc_interval = max_duration_of_gc * ((assumed_throughput_drop_during_gc / acceptable_throughput_drop) - 1.0); |
176 const double time_until_gc = acceptable_gc_interval - time_since_last_gc; |
176 const double time_until_gc = acceptable_gc_interval - time_since_last_gc; |
177 |
177 |
178 log_debug(gc, director)("Rule: Proactive, AcceptableGCInterval: %.3lfs, TimeSinceLastGC: %.3lfs, TimeUntilGC: %.3lfs", |
178 log_debug(gc, director)("Rule: Proactive, AcceptableGCInterval: %.3fs, TimeSinceLastGC: %.3fs, TimeUntilGC: %.3fs", |
179 acceptable_gc_interval, time_since_last_gc, time_until_gc); |
179 acceptable_gc_interval, time_since_last_gc, time_until_gc); |
180 |
180 |
181 return time_until_gc <= 0; |
181 return time_until_gc <= 0; |
182 } |
182 } |
183 |
183 |
189 // we start a GC cycle to avoid a potential allocation stall later. |
189 // we start a GC cycle to avoid a potential allocation stall later. |
190 |
190 |
191 // Calculate amount of free memory available to Java threads. Note that |
191 // Calculate amount of free memory available to Java threads. Note that |
192 // the heap reserve is not available to Java threads and is therefore not |
192 // the heap reserve is not available to Java threads and is therefore not |
193 // considered part of the free memory. |
193 // considered part of the free memory. |
194 const size_t max_capacity = ZHeap::heap()->current_max_capacity(); |
194 const size_t max_capacity = ZHeap::heap()->soft_max_capacity(); |
195 const size_t max_reserve = ZHeap::heap()->max_reserve(); |
195 const size_t max_reserve = ZHeap::heap()->max_reserve(); |
196 const size_t used = ZHeap::heap()->used(); |
196 const size_t used = ZHeap::heap()->used(); |
197 const size_t free_with_reserve = max_capacity - used; |
197 const size_t free_with_reserve = max_capacity - used; |
198 const size_t free = free_with_reserve - MIN2(free_with_reserve, max_reserve); |
198 const size_t free = free_with_reserve - MIN2(free_with_reserve, max_reserve); |
199 |
199 const double free_percent = percent_of(free, max_capacity); |
200 return percent_of(free, max_capacity) <= 5.0; |
200 |
|
201 log_debug(gc, director)("Rule: High Usage, Free: " SIZE_FORMAT "MB(%.1f%%)", |
|
202 free / M, free_percent); |
|
203 |
|
204 return free_percent <= 5.0; |
201 } |
205 } |
202 |
206 |
203 GCCause::Cause ZDirector::make_gc_decision() const { |
207 GCCause::Cause ZDirector::make_gc_decision() const { |
204 // Rule 0: Timer |
208 // Rule 0: Timer |
205 if (rule_timer()) { |
209 if (rule_timer()) { |