diff options
Diffstat (limited to 'src/runtime')
| -rw-r--r-- | src/runtime/mgc.go | 13 | ||||
| -rw-r--r-- | src/runtime/mgcscavenge.go | 2 | ||||
| -rw-r--r-- | src/runtime/mstats.go | 10 | ||||
| -rw-r--r-- | src/runtime/trace.go | 5 |
4 files changed, 19 insertions, 11 deletions
diff --git a/src/runtime/mgc.go b/src/runtime/mgc.go index 4b9a6da3b3..5c565a5853 100644 --- a/src/runtime/mgc.go +++ b/src/runtime/mgc.go @@ -409,7 +409,8 @@ type gcControllerState struct { } // startCycle resets the GC controller's state and computes estimates -// for a new GC cycle. The caller must hold worldsema. +// for a new GC cycle. The caller must hold worldsema and the world +// must be stopped. func (c *gcControllerState) startCycle() { c.scanWork = 0 c.bgScanCredit = 0 @@ -499,7 +500,7 @@ func (c *gcControllerState) revise() { // Assume we're under the soft goal. Pace GC to complete at // next_gc assuming the heap is in steady-state. - heapGoal := int64(memstats.next_gc) + heapGoal := int64(atomic.Load64(&memstats.next_gc)) // Compute the expected scan work remaining. // @@ -512,12 +513,12 @@ func (c *gcControllerState) revise() { // 100*heap_scan.) scanWorkExpected := int64(float64(scan) * 100 / float64(100+gcpercent)) - if live > memstats.next_gc || work > scanWorkExpected { + if int64(live) > heapGoal || work > scanWorkExpected { // We're past the soft goal, or we've already done more scan // work than we expected. Pace GC so that in the worst case it // will complete by the hard goal. const maxOvershoot = 1.1 - heapGoal = int64(float64(memstats.next_gc) * maxOvershoot) + heapGoal = int64(float64(heapGoal) * maxOvershoot) // Compute the upper bound on the scan work remaining. scanWorkExpected = int64(scan) @@ -846,7 +847,7 @@ func gcSetTriggerRatio(triggerRatio float64) { // Commit to the trigger and goal. memstats.gc_trigger = trigger - memstats.next_gc = goal + atomic.Store64(&memstats.next_gc, goal) if trace.enabled { traceNextGC() } @@ -903,7 +904,7 @@ func gcSetTriggerRatio(triggerRatio float64) { // // mheap_.lock must be held or the world must be stopped. func gcEffectiveGrowthRatio() float64 { - egogc := float64(memstats.next_gc-memstats.heap_marked) / float64(memstats.heap_marked) + egogc := float64(atomic.Load64(&memstats.next_gc)-memstats.heap_marked) / float64(memstats.heap_marked) if egogc < 0 { // Shouldn't happen, but just in case. egogc = 0 diff --git a/src/runtime/mgcscavenge.go b/src/runtime/mgcscavenge.go index 34646828e5..6328b295ca 100644 --- a/src/runtime/mgcscavenge.go +++ b/src/runtime/mgcscavenge.go @@ -123,7 +123,7 @@ func gcPaceScavenger() { return } // Compute our scavenging goal. - goalRatio := float64(memstats.next_gc) / float64(memstats.last_next_gc) + goalRatio := float64(atomic.Load64(&memstats.next_gc)) / float64(memstats.last_next_gc) retainedGoal := uint64(float64(memstats.last_heap_inuse) * goalRatio) // Add retainExtraPercent overhead to retainedGoal. This calculation // looks strange but the purpose is to arrive at an integer division diff --git a/src/runtime/mstats.go b/src/runtime/mstats.go index 2c217ecf84..8cc20552fb 100644 --- a/src/runtime/mstats.go +++ b/src/runtime/mstats.go @@ -57,9 +57,15 @@ type mstats struct { gc_sys uint64 // updated atomically or during STW other_sys uint64 // updated atomically or during STW - // Statistics about garbage collector. + // Statistics about the garbage collector. + + // next_gc is the goal heap_live for when next GC ends. + // Set to ^uint64(0) if disabled. + // + // Read and written atomically, unless the world is stopped. + next_gc uint64 + // Protected by mheap or stopping the world during GC. - next_gc uint64 // goal heap_live for when next GC ends; ^0 if disabled last_gc_unix uint64 // last gc (in unix time) pause_total_ns uint64 pause_ns [256]uint64 // circular buffer of recent gc pause lengths diff --git a/src/runtime/trace.go b/src/runtime/trace.go index 169b650eb4..d3ecd148be 100644 --- a/src/runtime/trace.go +++ b/src/runtime/trace.go @@ -13,6 +13,7 @@ package runtime import ( + "runtime/internal/atomic" "runtime/internal/sys" "unsafe" ) @@ -1146,11 +1147,11 @@ func traceHeapAlloc() { } func traceNextGC() { - if memstats.next_gc == ^uint64(0) { + if nextGC := atomic.Load64(&memstats.next_gc); nextGC == ^uint64(0) { // Heap-based triggering is disabled. traceEvent(traceEvNextGC, -1, 0) } else { - traceEvent(traceEvNextGC, -1, memstats.next_gc) + traceEvent(traceEvNextGC, -1, nextGC) } } |