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| author | Mathieu Chartier <mathieuc@google.com> | 2014-04-08 13:44:04 -0700 |
|---|---|---|
| committer | Mathieu Chartier <mathieuc@google.com> | 2014-04-09 09:39:40 -0700 |
| commit | df86d1f8147a95c1ec2f0c5d85e0439ef7d71730 (patch) | |
| tree | f4a38e6ac39f9a583ea9cf12ffe988e7687fc65a /runtime/gc | |
| parent | f2a26adf8d8573ab1d63e22290a600c350dc0f89 (diff) | |
| download | art-df86d1f8147a95c1ec2f0c5d85e0439ef7d71730.zip art-df86d1f8147a95c1ec2f0c5d85e0439ef7d71730.tar.gz art-df86d1f8147a95c1ec2f0c5d85e0439ef7d71730.tar.bz2 | |
Adjust sticky GC ergonomics.
Added an adjustment factor that causes sticky GC to occur more often.
Currently, we adjust the throughput by 5 / 4 comapred to the non
sticky GC. This improves the MemAllocTest score by 50-100. I believe
this happens since the sticky GC uses less memory bandwidth than
partial/full GC. No benchmark score regression on
EvaluateAndApplyChanges though total GC time is increased by ~0.5s.
Bug: 13818507
Change-Id: Ic721a1bff069ddaf8acc55e776b8bc26e171d46e
Diffstat (limited to 'runtime/gc')
| -rw-r--r-- | runtime/gc/heap.cc | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/runtime/gc/heap.cc b/runtime/gc/heap.cc index feb7a48..34a122f 100644 --- a/runtime/gc/heap.cc +++ b/runtime/gc/heap.cc @@ -77,6 +77,10 @@ static constexpr size_t kGcAlotInterval = KB; // Minimum amount of remaining bytes before a concurrent GC is triggered. static constexpr size_t kMinConcurrentRemainingBytes = 128 * KB; static constexpr size_t kMaxConcurrentRemainingBytes = 512 * KB; +// Sticky GC throughput adjustment, divided by 4. Increasing this causes sticky GC to occur more +// relative to partial/full GC. This is desirable since sticky GCs interfere less with mutator +// threads (lower pauses, use less memory bandwidth). +static constexpr double kStickyGcThroughputAdjustment = 1.25; Heap::Heap(size_t initial_size, size_t growth_limit, size_t min_free, size_t max_free, double target_utilization, size_t capacity, const std::string& image_file_name, @@ -2548,7 +2552,7 @@ void Heap::GrowForUtilization(collector::GarbageCollector* collector_ran) { // We also check that the bytes allocated aren't over the footprint limit in order to prevent a // pathological case where dead objects which aren't reclaimed by sticky could get accumulated // if the sticky GC throughput always remained >= the full/partial throughput. - if (collector_ran->GetEstimatedLastIterationThroughput() >= + if (collector_ran->GetEstimatedLastIterationThroughput() * kStickyGcThroughputAdjustment >= non_sticky_collector->GetEstimatedMeanThroughput() && non_sticky_collector->GetIterations() > 0 && bytes_allocated <= max_allowed_footprint_) { |