Add monitor deflation.
We now deflate the monitors when we perform a heap trim. This causes
a pause but it shouldn't matter since we should be in a state where
we don't care about pauses. Memory savings are hard to measure.
Fixed integer overflow bug in GetEstimatedLastIterationThroughput.
Bug: 13733906
Change-Id: I4e0e68add02e7f43370b3a5ea763d6fe8a5b212c
diff --git a/runtime/gc/heap.cc b/runtime/gc/heap.cc
index 915e54f..e3fa834 100644
--- a/runtime/gc/heap.cc
+++ b/runtime/gc/heap.cc
@@ -914,8 +914,16 @@
// Transition the collector if the desired collector type is not the same as the current
// collector type.
TransitionCollector(desired_collector_type);
- // Do a heap trim if it is needed.
- Trim();
+ if (!CareAboutPauseTimes()) {
+ // Deflate the monitors, this can cause a pause but shouldn't matter since we don't care
+ // about pauses.
+ Runtime* runtime = Runtime::Current();
+ runtime->GetThreadList()->SuspendAll();
+ runtime->GetMonitorList()->DeflateMonitors();
+ runtime->GetThreadList()->ResumeAll();
+ // Do a heap trim if it is needed.
+ Trim();
+ }
}
void Heap::Trim() {
@@ -2663,6 +2671,10 @@
}
void Heap::RequestHeapTrim() {
+ // Request a heap trim only if we do not currently care about pause times.
+ if (CareAboutPauseTimes()) {
+ return;
+ }
// GC completed and now we must decide whether to request a heap trim (advising pages back to the
// kernel) or not. Issuing a request will also cause trimming of the libc heap. As a trim scans
// a space it will hold its lock and can become a cause of jank.
@@ -2684,21 +2696,17 @@
// as we don't hold the lock while requesting the trim).
return;
}
-
- // Request a heap trim only if we do not currently care about pause times.
- if (!CareAboutPauseTimes()) {
- {
- MutexLock mu(self, *heap_trim_request_lock_);
- if (last_trim_time_ + kHeapTrimWait >= NanoTime()) {
- // We have done a heap trim in the last kHeapTrimWait nanosecs, don't request another one
- // just yet.
- return;
- }
- heap_trim_request_pending_ = true;
+ {
+ MutexLock mu(self, *heap_trim_request_lock_);
+ if (last_trim_time_ + kHeapTrimWait >= NanoTime()) {
+ // We have done a heap trim in the last kHeapTrimWait nanosecs, don't request another one
+ // just yet.
+ return;
}
- // Notify the daemon thread which will actually do the heap trim.
- SignalHeapTrimDaemon(self);
+ heap_trim_request_pending_ = true;
}
+ // Notify the daemon thread which will actually do the heap trim.
+ SignalHeapTrimDaemon(self);
}
void Heap::SignalHeapTrimDaemon(Thread* self) {