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-rw-r--r--8004-runtime-change-gcBackgroundUtilization-optional.patch442
1 files changed, 0 insertions, 442 deletions
diff --git a/8004-runtime-change-gcBackgroundUtilization-optional.patch b/8004-runtime-change-gcBackgroundUtilization-optional.patch
deleted file mode 100644
index 978c028..0000000
--- a/8004-runtime-change-gcBackgroundUtilization-optional.patch
+++ /dev/null
@@ -1,442 +0,0 @@
-From b270dd5d3dc1cef48866a9b29d26a3745e5dee67 Mon Sep 17 00:00:00 2001
-From: jinye <jinye10@huawei.com>
-Date: Wed, 6 Aug 2025 17:20:28 +0800
-Subject: [PATCH] runtime:change gcBackgroundUtilization optional
-
----
- src/runtime/export_test.go | 9 ++--
- src/runtime/mgc.go | 8 ++--
- src/runtime/mgclimit.go | 2 +-
- src/runtime/mgclimit_test.go | 12 +++---
- src/runtime/mgcpacer.go | 80 +++++++++++++++++++++++-------------
- src/runtime/mgcpacer_test.go | 24 ++++++++++-
- 6 files changed, 90 insertions(+), 45 deletions(-)
-
-diff --git a/src/runtime/export_test.go b/src/runtime/export_test.go
-index 79d83b3a..29341dd2 100644
---- a/src/runtime/export_test.go
-+++ b/src/runtime/export_test.go
-@@ -1324,25 +1324,26 @@ func GCTestPointerClass(p unsafe.Pointer) string {
- const Raceenabled = raceenabled
-
- const (
-- GCBackgroundUtilization = gcBackgroundUtilization
-- GCGoalUtilization = gcGoalUtilization
- DefaultHeapMinimum = defaultHeapMinimum
- MemoryLimitHeapGoalHeadroomPercent = memoryLimitHeapGoalHeadroomPercent
- MemoryLimitMinHeapGoalHeadroom = memoryLimitMinHeapGoalHeadroom
- )
-
-+var GCBackgroundUtilization = gcController.gcRatio
-+var GCGoalUtilization = gcGoalUtilization
-+
- type GCController struct {
- gcControllerState
- }
-
--func NewGCController(gcPercent int, memoryLimit int64) *GCController {
-+func NewGCController(gcPercent int, memoryLimit int64, gcRatio float64) *GCController {
- // Force the controller to escape. We're going to
- // do 64-bit atomics on it, and if it gets stack-allocated
- // on a 32-bit architecture, it may get allocated unaligned
- // space.
- g := Escape(new(GCController))
- g.gcControllerState.test = true // Mark it as a test copy.
-- g.init(int32(gcPercent), memoryLimit)
-+ g.init(int32(gcPercent), memoryLimit, gcRatio)
- return g
- }
-
-diff --git a/src/runtime/mgc.go b/src/runtime/mgc.go
-index 48001cfd..b8646679 100644
---- a/src/runtime/mgc.go
-+++ b/src/runtime/mgc.go
-@@ -184,7 +184,7 @@ func gcinit() {
- // Initialize GC pacer state.
- // Use the environment variable GOGC for the initial gcPercent value.
- // Use the environment variable GOMEMLIMIT for the initial memoryLimit value.
-- gcController.init(readGOGC(), readGOMEMLIMIT())
-+ gcController.init(readGOGC(), readGOMEMLIMIT(), readGOGCRATIO())
-
- work.startSema = 1
- work.markDoneSema = 1
-@@ -270,12 +270,12 @@ const (
-
- // gcMarkWorkerFractionalMode indicates that a P is currently
- // running the "fractional" mark worker. The fractional worker
-- // is necessary when GOMAXPROCS*gcBackgroundUtilization is not
-+ // is necessary when GOMAXPROCS*gcController.gcRatio is not
- // an integer and using only dedicated workers would result in
-- // utilization too far from the target of gcBackgroundUtilization.
-+ // utilization too far from the target of gcController.gcRatio.
- // The fractional worker should run until it is preempted and
- // will be scheduled to pick up the fractional part of
-- // GOMAXPROCS*gcBackgroundUtilization.
-+ // GOMAXPROCS*gcController.gcRatio.
- gcMarkWorkerFractionalMode
-
- // gcMarkWorkerIdleMode indicates that a P is running the mark
-diff --git a/src/runtime/mgclimit.go b/src/runtime/mgclimit.go
-index ad86fbd6..ae35ee8d 100644
---- a/src/runtime/mgclimit.go
-+++ b/src/runtime/mgclimit.go
-@@ -230,7 +230,7 @@ func (l *gcCPULimiterState) updateLocked(now int64) {
- // Compute total GC time.
- windowGCTime := assistTime
- if l.gcEnabled {
-- windowGCTime += int64(float64(windowTotalTime) * gcBackgroundUtilization)
-+ windowGCTime += int64(float64(windowTotalTime) * gcController.gcRatio)
- }
-
- // Subtract out all idle time from the total time. Do this after computing
-diff --git a/src/runtime/mgclimit_test.go b/src/runtime/mgclimit_test.go
-index 124da03e..8d3eaa6b 100644
---- a/src/runtime/mgclimit_test.go
-+++ b/src/runtime/mgclimit_test.go
-@@ -76,13 +76,13 @@ func TestGCCPULimiter(t *testing.T) {
- // Test passing time without assists during a GC. Specifically, just enough to drain the bucket to
- // exactly procs nanoseconds (easier to get to because of rounding).
- //
-- // The window we need to drain the bucket is 1/(1-2*gcBackgroundUtilization) times the current fill:
-+ // The window we need to drain the bucket is 1/(1-2*gcController.gcRatio) times the current fill:
- //
-- // fill + (window * procs * gcBackgroundUtilization - window * procs * (1-gcBackgroundUtilization)) = n
-- // fill = n - (window * procs * gcBackgroundUtilization - window * procs * (1-gcBackgroundUtilization))
-- // fill = n + window * procs * ((1-gcBackgroundUtilization) - gcBackgroundUtilization)
-- // fill = n + window * procs * (1-2*gcBackgroundUtilization)
-- // window = (fill - n) / (procs * (1-2*gcBackgroundUtilization)))
-+ // fill + (window * procs * gcController.gcRatio - window * procs * (1-gcController.gcRatio)) = n
-+ // fill = n - (window * procs * gcController.gcRatio - window * procs * (1-gcController.gcRatio))
-+ // fill = n + window * procs * ((1-gcController.gcRatio) - gcController.gcRatio)
-+ // fill = n + window * procs * (1-2*gcController.gcRatio)
-+ // window = (fill - n) / (procs * (1-2*gcController.gcRatio)))
- //
- // And here we want n=procs:
- factor := (1 / (1 - 2*GCBackgroundUtilization))
-diff --git a/src/runtime/mgcpacer.go b/src/runtime/mgcpacer.go
-index 3e80fae4..20630c3f 100644
---- a/src/runtime/mgcpacer.go
-+++ b/src/runtime/mgcpacer.go
-@@ -12,30 +12,6 @@ import (
- )
-
- const (
-- // gcGoalUtilization is the goal CPU utilization for
-- // marking as a fraction of GOMAXPROCS.
-- //
-- // Increasing the goal utilization will shorten GC cycles as the GC
-- // has more resources behind it, lessening costs from the write barrier,
-- // but comes at the cost of increasing mutator latency.
-- gcGoalUtilization = gcBackgroundUtilization
--
-- // gcBackgroundUtilization is the fixed CPU utilization for background
-- // marking. It must be <= gcGoalUtilization. The difference between
-- // gcGoalUtilization and gcBackgroundUtilization will be made up by
-- // mark assists. The scheduler will aim to use within 50% of this
-- // goal.
-- //
-- // As a general rule, there's little reason to set gcBackgroundUtilization
-- // < gcGoalUtilization. One reason might be in mostly idle applications,
-- // where goroutines are unlikely to assist at all, so the actual
-- // utilization will be lower than the goal. But this is moot point
-- // because the idle mark workers already soak up idle CPU resources.
-- // These two values are still kept separate however because they are
-- // distinct conceptually, and in previous iterations of the pacer the
-- // distinction was more important.
-- gcBackgroundUtilization = 0.25
--
- // gcCreditSlack is the amount of scan work credit that can
- // accumulate locally before updating gcController.heapScanWork and,
- // optionally, gcController.bgScanCredit. Lower values give a more
-@@ -72,6 +48,15 @@ const (
- // to maintain the memory limit.
- memoryLimitHeapGoalHeadroomPercent = 3
- )
-+// gcGoalUtilization is the goal CPU utilization for
-+// marking as a fraction of GOMAXPROCS.
-+//
-+// Increasing the goal utilization will shorten GC cycles as the GC
-+// has more resources behind it, lessening costs from the write barrier,
-+// but comes at the cost of increasing mutator latency.
-+var gcGoalUtilization = gcController.gcRatio
-+
-+
-
- // gcController implements the GC pacing controller that determines
- // when to trigger concurrent garbage collection and how much marking
-@@ -88,6 +73,11 @@ const (
- var gcController gcControllerState
-
- type gcControllerState struct {
-+ // gcController.gcRatio be optional, value equals gcratio/100.0.
-+ // Initialized from GOGCRATIO, which in the range of (1, 99).
-+ // Default GOGCRATIO is 25.
-+ gcRatio float64
-+
- // Initialized from GOGC. GOGC=off means no GC.
- gcPercent atomic.Int32
-
-@@ -366,11 +356,12 @@ type gcControllerState struct {
- _ cpu.CacheLinePad
- }
-
--func (c *gcControllerState) init(gcPercent int32, memoryLimit int64) {
-+func (c *gcControllerState) init(gcPercent int32, memoryLimit int64, gcRatio float64) {
- c.heapMinimum = defaultHeapMinimum
- c.triggered = ^uint64(0)
- c.setGCPercent(gcPercent)
- c.setMemoryLimit(memoryLimit)
-+ c.setGOGCRatio(gcRatio)
- c.commit(true) // No sweep phase in the first GC cycle.
- // N.B. Don't bother calling traceHeapGoal. Tracing is never enabled at
- // initialization time.
-@@ -398,13 +389,13 @@ func (c *gcControllerState) startCycle(markStartTime int64, procs int, trigger g
- // dedicated workers so that the utilization is closest to
- // 25%. For small GOMAXPROCS, this would introduce too much
- // error, so we add fractional workers in that case.
-- totalUtilizationGoal := float64(procs) * gcBackgroundUtilization
-+ totalUtilizationGoal := float64(procs) * gcController.gcRatio
- dedicatedMarkWorkersNeeded := int64(totalUtilizationGoal + 0.5)
- utilError := float64(dedicatedMarkWorkersNeeded)/totalUtilizationGoal - 1
- const maxUtilError = 0.3
- if utilError < -maxUtilError || utilError > maxUtilError {
- // Rounding put us more than 30% off our goal. With
-- // gcBackgroundUtilization of 25%, this happens for
-+ // gcController.gcRatio of 25%, this happens for
- // GOMAXPROCS<=3 or GOMAXPROCS=6. Enable fractional
- // workers to compensate.
- if float64(dedicatedMarkWorkersNeeded) > totalUtilizationGoal {
-@@ -604,7 +595,7 @@ func (c *gcControllerState) endCycle(now int64, procs int, userForced bool) {
- assistDuration := now - c.markStartTime
-
- // Assume background mark hit its utilization goal.
-- utilization := gcBackgroundUtilization
-+ utilization := gcController.gcRatio
- // Add assist utilization; avoid divide by zero.
- if assistDuration > 0 {
- utilization += float64(c.assistTime.Load()) / float64(assistDuration*int64(procs))
-@@ -1344,6 +1335,39 @@ func readGOMEMLIMIT() int64 {
- return n
- }
-
-+func (c *gcControllerState) setGOGCRatio(in float64) float64 {
-+ if !c.test {
-+ assertWorldStoppedOrLockHeld(&mheap_.lock)
-+ }
-+
-+ out := c.gcRatio
-+ c.gcRatio = in
-+
-+ return out
-+}
-+
-+func readGOGCRATIO() float64 {
-+ p := gogetenv("GOGCRATIO")
-+ if p == "" {
-+ return 0.25
-+ }
-+ n, ok := parseByteCount(p)
-+ if !ok {
-+ print("GOGCRATIO=", p, "\n")
-+ throw("malformed GOGCRATIO; get the wrong value")
-+ }
-+
-+ if n < 1 {
-+ n = 1
-+ } else if n > 99 {
-+ n = 99
-+ }
-+
-+ out := float64(n)/100.0
-+
-+ return out
-+}
-+
- // addIdleMarkWorker attempts to add a new idle mark worker.
- //
- // If this returns true, the caller must become an idle mark worker unless
-diff --git a/src/runtime/mgcpacer_test.go b/src/runtime/mgcpacer_test.go
-index ef1483d6..32d4943c 100644
---- a/src/runtime/mgcpacer_test.go
-+++ b/src/runtime/mgcpacer_test.go
-@@ -24,6 +24,7 @@ func TestGcPacer(t *testing.T) {
- name: "Steady",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(33.0),
-@@ -49,6 +50,7 @@ func TestGcPacer(t *testing.T) {
- name: "SteadyBigStacks",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(132.0),
-@@ -77,6 +79,7 @@ func TestGcPacer(t *testing.T) {
- name: "SteadyBigGlobals",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 128 << 20,
- nCores: 8,
- allocRate: constant(132.0),
-@@ -105,6 +108,7 @@ func TestGcPacer(t *testing.T) {
- name: "StepAlloc",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(33.0).sum(ramp(66.0, 1).delay(50)),
-@@ -128,6 +132,7 @@ func TestGcPacer(t *testing.T) {
- name: "HeavyStepAlloc",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(33).sum(ramp(330, 1).delay(50)),
-@@ -151,6 +156,7 @@ func TestGcPacer(t *testing.T) {
- name: "StepScannableFrac",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(128.0),
-@@ -176,6 +182,7 @@ func TestGcPacer(t *testing.T) {
- name: "HighGOGC",
- gcPercent: 1500,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: random(7, 0x53).offset(165),
-@@ -217,6 +224,7 @@ func TestGcPacer(t *testing.T) {
- name: "OscAlloc",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: oscillate(13, 0, 8).offset(67),
-@@ -241,6 +249,7 @@ func TestGcPacer(t *testing.T) {
- name: "JitterAlloc",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: random(13, 0xf).offset(132),
-@@ -266,6 +275,7 @@ func TestGcPacer(t *testing.T) {
- name: "HeavyJitterAlloc",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: random(33.0, 0x0).offset(330),
-@@ -295,6 +305,7 @@ func TestGcPacer(t *testing.T) {
- name: "SmallHeapSlowAlloc",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(1.0),
-@@ -332,6 +343,7 @@ func TestGcPacer(t *testing.T) {
- name: "MediumHeapSlowAlloc",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(1.0),
-@@ -369,6 +381,7 @@ func TestGcPacer(t *testing.T) {
- name: "LargeHeapSlowAlloc",
- gcPercent: 100,
- memoryLimit: math.MaxInt64,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(1.0),
-@@ -407,6 +420,7 @@ func TestGcPacer(t *testing.T) {
- name: "SteadyMemoryLimit",
- gcPercent: 100,
- memoryLimit: 512 << 20,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(33.0),
-@@ -436,6 +450,7 @@ func TestGcPacer(t *testing.T) {
- name: "SteadyMemoryLimitNoGCPercent",
- gcPercent: -1,
- memoryLimit: 512 << 20,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(33.0),
-@@ -465,6 +480,7 @@ func TestGcPacer(t *testing.T) {
- name: "ExceedMemoryLimit",
- gcPercent: 100,
- memoryLimit: 512 << 20,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(33.0),
-@@ -499,6 +515,7 @@ func TestGcPacer(t *testing.T) {
- name: "ExceedMemoryLimitNoGCPercent",
- gcPercent: -1,
- memoryLimit: 512 << 20,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(33.0),
-@@ -538,6 +555,7 @@ func TestGcPacer(t *testing.T) {
- name: "MaintainMemoryLimit",
- gcPercent: 100,
- memoryLimit: 512 << 20,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(33.0),
-@@ -571,6 +589,7 @@ func TestGcPacer(t *testing.T) {
- name: "MaintainMemoryLimitNoGCPercent",
- gcPercent: -1,
- memoryLimit: 512 << 20,
-+ gcRatio: 0.25,
- globalsBytes: 32 << 10,
- nCores: 8,
- allocRate: constant(33.0),
-@@ -607,7 +626,7 @@ func TestGcPacer(t *testing.T) {
- t.Run(e.name, func(t *testing.T) {
- t.Parallel()
-
-- c := NewGCController(e.gcPercent, e.memoryLimit)
-+ c := NewGCController(e.gcPercent, e.memoryLimit, e.gcRatio)
- var bytesAllocatedBlackLast int64
- results := make([]gcCycleResult, 0, e.length)
- for i := 0; i < e.length; i++ {
-@@ -762,6 +781,7 @@ type gcExecTest struct {
-
- gcPercent int
- memoryLimit int64
-+ gcRatio float64
- globalsBytes uint64
- nCores int
-
-@@ -1034,7 +1054,7 @@ func applyMemoryLimitHeapGoalHeadroom(goal uint64) uint64 {
-
- func TestIdleMarkWorkerCount(t *testing.T) {
- const workers = 10
-- c := NewGCController(100, math.MaxInt64)
-+ c := NewGCController(100, math.MaxInt64, 0.25)
- c.SetMaxIdleMarkWorkers(workers)
- for i := 0; i < workers; i++ {
- if !c.NeedIdleMarkWorker() {
---
-2.33.0
-
generated by cgit v1.2.3 (git 2.25.1) at 2025-09-01 15:19:21 +0000