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Rename width to workEstimate in P&F code 

Kubernetes-commit: 73211256e8f15cf84ee69d6fe8258c3a912e0f94
This commit is contained in:
wojtekt 2021-07-13 15:10:58 +02:00 committed by Kubernetes Publisher
parent 4feaaf7955
commit b4c306e1e8
13 changed files with 69 additions and 68 deletions
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10
pkg/server/config.go
View File

@ -222,9 +222,6 @@ type Config struct {
// If not specify any in flags, then genericapiserver will only enable defaultAPIResourceConfig.
MergedResourceConfig *serverstore.ResourceConfig
// RequestWidthEstimator is used to estimate the "width" of the incoming request(s).
RequestWidthEstimator flowcontrolrequest.WidthEstimatorFunc
// lifecycleSignals provides access to the various signals
// that happen during lifecycle of the apiserver.
// it's intentionally marked private as it should never be overridden.
@ -352,9 +349,8 @@ func NewConfig(codecs serializer.CodecFactory) *Config {
// Default to treating watch as a long-running operation
// Generic API servers have no inherent long-running subresources
LongRunningFunc: genericfilters.BasicLongRunningRequestCheck(sets.NewString("watch"), sets.NewString()),
RequestWidthEstimator: flowcontrolrequest.DefaultWidthEstimator,
lifecycleSignals: newLifecycleSignals(),
LongRunningFunc: genericfilters.BasicLongRunningRequestCheck(sets.NewString("watch"), sets.NewString()),
lifecycleSignals: newLifecycleSignals(),
APIServerID: id,
StorageVersionManager: storageversion.NewDefaultManager(),
@ -747,7 +743,7 @@ func DefaultBuildHandlerChain(apiHandler http.Handler, c *Config) http.Handler {
if c.FlowControl != nil {
handler = filterlatency.TrackCompleted(handler)
handler = genericfilters.WithPriorityAndFairness(handler, c.LongRunningFunc, c.FlowControl, c.RequestWidthEstimator)
handler = genericfilters.WithPriorityAndFairness(handler, c.LongRunningFunc, c.FlowControl, flowcontrolrequest.DefaultWorkEstimator)
handler = filterlatency.TrackStarted(handler, "priorityandfairness")
} else {
handler = genericfilters.WithMaxInFlightLimit(handler, c.MaxRequestsInFlight, c.MaxMutatingRequestsInFlight, c.LongRunningFunc)

13
pkg/server/filters/priority-and-fairness.go
View File

@ -61,7 +61,7 @@ func WithPriorityAndFairness(
handler http.Handler,
longRunningRequestCheck apirequest.LongRunningRequestCheck,
fcIfc utilflowcontrol.Interface,
widthEstimator flowcontrolrequest.WidthEstimatorFunc,
workEstimator flowcontrolrequest.WorkEstimatorFunc,
) http.Handler {
if fcIfc == nil {
klog.Warningf("priority and fairness support not found, skipping")
@ -122,11 +122,14 @@ func WithPriorityAndFairness(
}
}
// find the estimated "width" of the request
// TODO: Maybe just make it costEstimator and let it return additionalLatency too for the watch?
// find the estimated amount of work of the request
// TODO: Estimate cost should also take fcIfc.GetWatchCount(requestInfo) as a parameter.
width := widthEstimator.EstimateWidth(r)
digest := utilflowcontrol.RequestDigest{RequestInfo: requestInfo, User: user, Width: width}
workEstimate := workEstimator.EstimateWork(r)
digest := utilflowcontrol.RequestDigest{
RequestInfo: requestInfo,
User: user,
WorkEstimate: workEstimate,
}
if isWatchRequest {
// This channel blocks calling handler.ServeHTTP() until closed, and is closed inside execute().

12
pkg/server/filters/priority-and-fairness_test.go
View File

@ -70,7 +70,9 @@ const (
decisionSkipFilter
)
var defaultRequestWidthEstimator = func(*http.Request) fcrequest.Width { return fcrequest.Width{Seats: 1} }
var defaultRequestWorkEstimator = func(*http.Request) fcrequest.WorkEstimate {
return fcrequest.WorkEstimate{Seats: 1}
}
type fakeApfFilter struct {
mockDecision mockDecision
@ -165,7 +167,7 @@ func newApfHandlerWithFilter(t *testing.T, flowControlFilter utilflowcontrol.Int
apfHandler := WithPriorityAndFairness(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
onExecute()
}), longRunningRequestCheck, flowControlFilter, defaultRequestWidthEstimator)
}), longRunningRequestCheck, flowControlFilter, defaultRequestWorkEstimator)
handler := apifilters.WithRequestInfo(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
r = r.WithContext(apirequest.WithUser(r.Context(), &user.DefaultInfo{
@ -649,7 +651,7 @@ func TestApfWithRequestDigest(t *testing.T) {
reqDigestExpected := &utilflowcontrol.RequestDigest{
RequestInfo: &apirequest.RequestInfo{Verb: "get"},
User: &user.DefaultInfo{Name: "foo"},
Width: fcrequest.Width{
WorkEstimate: fcrequest.WorkEstimate{
Seats: 5,
},
}
@ -657,7 +659,7 @@ func TestApfWithRequestDigest(t *testing.T) {
handler := WithPriorityAndFairness(http.HandlerFunc(func(_ http.ResponseWriter, req *http.Request) {}),
longRunningFunc,
fakeFilter,
func(_ *http.Request) fcrequest.Width { return reqDigestExpected.Width },
func(_ *http.Request) fcrequest.WorkEstimate { return reqDigestExpected.WorkEstimate },
)
w := httptest.NewRecorder()
@ -1171,7 +1173,7 @@ func newHandlerChain(t *testing.T, handler http.Handler, filter utilflowcontrol.
requestInfoFactory := &apirequest.RequestInfoFactory{APIPrefixes: sets.NewString("apis", "api"), GrouplessAPIPrefixes: sets.NewString("api")}
longRunningRequestCheck := BasicLongRunningRequestCheck(sets.NewString("watch"), sets.NewString("proxy"))
apfHandler := WithPriorityAndFairness(handler, longRunningRequestCheck, filter, defaultRequestWidthEstimator)
apfHandler := WithPriorityAndFairness(handler, longRunningRequestCheck, filter, defaultRequestWorkEstimator)
// add the handler in the chain that adds the specified user to the request context
handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

8
pkg/util/flowcontrol/apf_controller.go
View File

@ -80,9 +80,9 @@ type StartFunction func(ctx context.Context, hashValue uint64) (execute bool, af
// RequestDigest holds necessary info from request for flow-control
type RequestDigest struct {
RequestInfo *request.RequestInfo
User user.Info
Width fcrequest.Width
RequestInfo *request.RequestInfo
User user.Info
WorkEstimate fcrequest.WorkEstimate
}
// `*configController` maintains eventual consistency with the API
@ -809,7 +809,7 @@ func (cfgCtlr *configController) startRequest(ctx context.Context, rd RequestDig
}
startWaitingTime = time.Now()
klog.V(7).Infof("startRequest(%#+v) => fsName=%q, distMethod=%#+v, plName=%q, numQueues=%d", rd, selectedFlowSchema.Name, selectedFlowSchema.Spec.DistinguisherMethod, plName, numQueues)
req, idle := plState.queues.StartRequest(ctx, &rd.Width, hashValue, flowDistinguisher, selectedFlowSchema.Name, rd.RequestInfo, rd.User, queueNoteFn)
req, idle := plState.queues.StartRequest(ctx, &rd.WorkEstimate, hashValue, flowDistinguisher, selectedFlowSchema.Name, rd.RequestInfo, rd.User, queueNoteFn)
if idle {
cfgCtlr.maybeReapLocked(plName, plState)
}

2
pkg/util/flowcontrol/controller_test.go
View File

@ -140,7 +140,7 @@ func (cqs *ctlrTestQueueSet) IsIdle() bool {
return cqs.countActive == 0
}
func (cqs *ctlrTestQueueSet) StartRequest(ctx context.Context, width *fcrequest.Width, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn fq.QueueNoteFn) (req fq.Request, idle bool) {
func (cqs *ctlrTestQueueSet) StartRequest(ctx context.Context, width *fcrequest.WorkEstimate, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn fq.QueueNoteFn) (req fq.Request, idle bool) {
cqs.cts.lock.Lock()
defer cqs.cts.lock.Unlock()
cqs.countActive++

2
pkg/util/flowcontrol/fairqueuing/interface.go
View File

@ -81,7 +81,7 @@ type QueueSet interface {
// was idle at the moment of the return. Otherwise idle==false
// and the client must call the Finish method of the Request
// exactly once.
StartRequest(ctx context.Context, width *request.Width, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn QueueNoteFn) (req Request, idle bool)
StartRequest(ctx context.Context, width *request.WorkEstimate, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn QueueNoteFn) (req Request, idle bool)
// UpdateObservations makes sure any time-based statistics have
// caught up with the current clock reading

2
pkg/util/flowcontrol/fairqueuing/queueset/fifo_list_test.go
View File

@ -154,7 +154,7 @@ func TestFIFOSeatsSum(t *testing.T) {
list := newRequestFIFO()
newRequest := func(width uint) *request {
return &request{width: fcrequest.Width{Seats: width}}
return &request{workEstimate: fcrequest.WorkEstimate{Seats: width}}
}
arrival := []*request{newRequest(1), newRequest(2), newRequest(3)}
removeFn := make([]removeFromFIFOFunc, 0)

22
pkg/util/flowcontrol/fairqueuing/queueset/queueset.go
View File

@ -235,7 +235,7 @@ const (
// executing at each point where there is a change in that quantity,
// because the metrics --- and only the metrics --- track that
// quantity per FlowSchema.
func (qs *queueSet) StartRequest(ctx context.Context, width *fqrequest.Width, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn fq.QueueNoteFn) (fq.Request, bool) {
func (qs *queueSet) StartRequest(ctx context.Context, workEstimate *fqrequest.WorkEstimate, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn fq.QueueNoteFn) (fq.Request, bool) {
qs.lockAndSyncTime()
defer qs.lock.Unlock()
var req *request
@ -244,13 +244,13 @@ func (qs *queueSet) StartRequest(ctx context.Context, width *fqrequest.Width, ha
// Step 0:
// Apply only concurrency limit, if zero queues desired
if qs.qCfg.DesiredNumQueues < 1 {
if !qs.canAccommodateSeatsLocked(int(width.Seats)) {
if !qs.canAccommodateSeatsLocked(int(workEstimate.Seats)) {
klog.V(5).Infof("QS(%s): rejecting request %q %#+v %#+v because %d seats are asked for, %d seats are in use (%d are executing) and the limit is %d",
qs.qCfg.Name, fsName, descr1, descr2, width, qs.totSeatsInUse, qs.totRequestsExecuting, qs.dCfg.ConcurrencyLimit)
qs.qCfg.Name, fsName, descr1, descr2, workEstimate, qs.totSeatsInUse, qs.totRequestsExecuting, qs.dCfg.ConcurrencyLimit)
metrics.AddReject(ctx, qs.qCfg.Name, fsName, "concurrency-limit")
return nil, qs.isIdleLocked()
}
req = qs.dispatchSansQueueLocked(ctx, width, flowDistinguisher, fsName, descr1, descr2)
req = qs.dispatchSansQueueLocked(ctx, workEstimate, flowDistinguisher, fsName, descr1, descr2)
return req, false
}
@ -261,7 +261,7 @@ func (qs *queueSet) StartRequest(ctx context.Context, width *fqrequest.Width, ha
// 3) Reject current request if there is not enough concurrency shares and
// we are at max queue length
// 4) If not rejected, create a request and enqueue
req = qs.timeoutOldRequestsAndRejectOrEnqueueLocked(ctx, width, hashValue, flowDistinguisher, fsName, descr1, descr2, queueNoteFn)
req = qs.timeoutOldRequestsAndRejectOrEnqueueLocked(ctx, workEstimate, hashValue, flowDistinguisher, fsName, descr1, descr2, queueNoteFn)
// req == nil means that the request was rejected - no remaining
// concurrency shares and at max queue length already
if req == nil {
@ -316,7 +316,7 @@ func (qs *queueSet) StartRequest(ctx context.Context, width *fqrequest.Width, ha
// Seats returns the number of seats this request requires.
func (req *request) Seats() int {
return int(req.width.Seats)
return int(req.workEstimate.Seats)
}
func (req *request) NoteQueued(inQueue bool) {
@ -437,7 +437,7 @@ func (qs *queueSet) getVirtualTimeRatioLocked() float64 {
// returns the enqueud request on a successful enqueue
// returns nil in the case that there is no available concurrency or
// the queuelengthlimit has been reached
func (qs *queueSet) timeoutOldRequestsAndRejectOrEnqueueLocked(ctx context.Context, width *fqrequest.Width, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn fq.QueueNoteFn) *request {
func (qs *queueSet) timeoutOldRequestsAndRejectOrEnqueueLocked(ctx context.Context, workEstimate *fqrequest.WorkEstimate, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn fq.QueueNoteFn) *request {
// Start with the shuffle sharding, to pick a queue.
queueIdx := qs.chooseQueueIndexLocked(hashValue, descr1, descr2)
queue := qs.queues[queueIdx]
@ -459,7 +459,7 @@ func (qs *queueSet) timeoutOldRequestsAndRejectOrEnqueueLocked(ctx context.Conte
descr1: descr1,
descr2: descr2,
queueNoteFn: queueNoteFn,
width: *width,
workEstimate: *workEstimate,
}
if ok := qs.rejectOrEnqueueLocked(req); !ok {
return nil
@ -476,7 +476,7 @@ func (qs *queueSet) chooseQueueIndexLocked(hashValue uint64, descr1, descr2 inte
// the dealer uses the current desired number of queues, which is no larger than the number in `qs.queues`.
qs.dealer.Deal(hashValue, func(queueIdx int) {
// TODO: Consider taking into account `additional latency` of requests
// in addition to their widths.
// in addition to their seats.
// Ideally, this should be based on projected completion time in the
// virtual world of the youngest request in the queue.
thisSeatsSum := qs.queues[queueIdx].requests.SeatsSum()
@ -579,7 +579,7 @@ func (qs *queueSet) dispatchAsMuchAsPossibleLocked() {
}
}
func (qs *queueSet) dispatchSansQueueLocked(ctx context.Context, width *fqrequest.Width, flowDistinguisher, fsName string, descr1, descr2 interface{}) *request {
func (qs *queueSet) dispatchSansQueueLocked(ctx context.Context, workEstimate *fqrequest.WorkEstimate, flowDistinguisher, fsName string, descr1, descr2 interface{}) *request {
// does not call metrics.SetDispatchMetrics because there is no queuing and thus no interesting virtual world
now := qs.clock.Now()
req := &request{
@ -592,7 +592,7 @@ func (qs *queueSet) dispatchSansQueueLocked(ctx context.Context, width *fqreques
arrivalTime: now,
descr1: descr1,
descr2: descr2,
width: *width,
workEstimate: *workEstimate,
}
req.decision.SetLocked(decisionExecute)
qs.totRequestsExecuting++

26
pkg/util/flowcontrol/fairqueuing/queueset/queueset_test.go
View File

@ -227,7 +227,7 @@ func (ust *uniformScenarioThread) callK(k int) {
if k >= ust.nCalls {
return
}
req, idle := ust.uss.qs.StartRequest(context.Background(), &fcrequest.Width{Seats: 1}, ust.uc.hash, "", ust.fsName, ust.uss.name, []int{ust.i, ust.j, k}, nil)
req, idle := ust.uss.qs.StartRequest(context.Background(), &fcrequest.WorkEstimate{Seats: 1}, ust.uc.hash, "", ust.fsName, ust.uss.name, []int{ust.i, ust.j, k}, nil)
ust.uss.t.Logf("%s: %d, %d, %d got req=%p, idle=%v", ust.uss.clk.Now().Format(nsTimeFmt), ust.i, ust.j, k, req, idle)
if req == nil {
atomic.AddUint64(&ust.uss.failedCount, 1)
@ -672,7 +672,7 @@ func TestContextCancel(t *testing.T) {
ctx1 := context.Background()
b2i := map[bool]int{false: 0, true: 1}
var qnc [2][2]int32
req1, _ := qs.StartRequest(ctx1, &fcrequest.Width{Seats: 1}, 1, "", "fs1", "test", "one", func(inQueue bool) { atomic.AddInt32(&qnc[0][b2i[inQueue]], 1) })
req1, _ := qs.StartRequest(ctx1, &fcrequest.WorkEstimate{Seats: 1}, 1, "", "fs1", "test", "one", func(inQueue bool) { atomic.AddInt32(&qnc[0][b2i[inQueue]], 1) })
if req1 == nil {
t.Error("Request rejected")
return
@ -700,7 +700,7 @@ func TestContextCancel(t *testing.T) {
counter.Add(1)
cancel2()
}()
req2, idle2a := qs.StartRequest(ctx2, &fcrequest.Width{Seats: 1}, 2, "", "fs2", "test", "two", func(inQueue bool) { atomic.AddInt32(&qnc[1][b2i[inQueue]], 1) })
req2, idle2a := qs.StartRequest(ctx2, &fcrequest.WorkEstimate{Seats: 1}, 2, "", "fs2", "test", "two", func(inQueue bool) { atomic.AddInt32(&qnc[1][b2i[inQueue]], 1) })
if idle2a {
t.Error("2nd StartRequest returned idle")
}
@ -759,7 +759,7 @@ func TestTotalRequestsExecutingWithPanic(t *testing.T) {
}
ctx := context.Background()
req, _ := qs.StartRequest(ctx, &fcrequest.Width{Seats: 1}, 1, "", "fs", "test", "one", func(inQueue bool) {})
req, _ := qs.StartRequest(ctx, &fcrequest.WorkEstimate{Seats: 1}, 1, "", "fs", "test", "one", func(inQueue bool) {})
if req == nil {
t.Fatal("expected a Request object from StartRequest, but got nil")
}
@ -812,13 +812,13 @@ func TestSelectQueueLocked(t *testing.T) {
{
virtualStart: 200,
requests: newFIFO(
&request{width: fcrequest.Width{Seats: 1}},
&request{workEstimate: fcrequest.WorkEstimate{Seats: 1}},
),
},
{
virtualStart: 100,
requests: newFIFO(
&request{width: fcrequest.Width{Seats: 1}},
&request{workEstimate: fcrequest.WorkEstimate{Seats: 1}},
),
},
},
@ -835,7 +835,7 @@ func TestSelectQueueLocked(t *testing.T) {
{
virtualStart: 200,
requests: newFIFO(
&request{width: fcrequest.Width{Seats: 1}},
&request{workEstimate: fcrequest.WorkEstimate{Seats: 1}},
),
},
},
@ -852,13 +852,13 @@ func TestSelectQueueLocked(t *testing.T) {
{
virtualStart: 200,
requests: newFIFO(
&request{width: fcrequest.Width{Seats: 50}},
&request{workEstimate: fcrequest.WorkEstimate{Seats: 50}},
),
},
{
virtualStart: 100,
requests: newFIFO(
&request{width: fcrequest.Width{Seats: 25}},
&request{workEstimate: fcrequest.WorkEstimate{Seats: 25}},
),
},
},
@ -875,13 +875,13 @@ func TestSelectQueueLocked(t *testing.T) {
{
virtualStart: 200,
requests: newFIFO(
&request{width: fcrequest.Width{Seats: 10}},
&request{workEstimate: fcrequest.WorkEstimate{Seats: 10}},
),
},
{
virtualStart: 100,
requests: newFIFO(
&request{width: fcrequest.Width{Seats: 25}},
&request{workEstimate: fcrequest.WorkEstimate{Seats: 25}},
),
},
},
@ -898,13 +898,13 @@ func TestSelectQueueLocked(t *testing.T) {
{
virtualStart: 200,
requests: newFIFO(
&request{width: fcrequest.Width{Seats: 10}},
&request{workEstimate: fcrequest.WorkEstimate{Seats: 10}},
),
},
{
virtualStart: 100,
requests: newFIFO(
&request{width: fcrequest.Width{Seats: 25}},
&request{workEstimate: fcrequest.WorkEstimate{Seats: 25}},
),
},
},

4
pkg/util/flowcontrol/fairqueuing/queueset/types.go
View File

@ -44,8 +44,8 @@ type request struct {
// startTime is the real time when the request began executing
startTime time.Time
// width of the request
width fcrequest.Width
// estimated amount of work of the request
workEstimate fcrequest.WorkEstimate
// decision gets set to a `requestDecision` indicating what to do
// with this request. It gets set exactly once, when the request

2
pkg/util/flowcontrol/fairqueuing/testing/no-restraint.go
View File

@ -56,7 +56,7 @@ func (noRestraint) IsIdle() bool {
return false
}
func (noRestraint) StartRequest(ctx context.Context, width *fcrequest.Width, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn fq.QueueNoteFn) (fq.Request, bool) {
func (noRestraint) StartRequest(ctx context.Context, workEstimate *fcrequest.WorkEstimate, hashValue uint64, flowDistinguisher, fsName string, descr1, descr2 interface{}, queueNoteFn fq.QueueNoteFn) (fq.Request, bool) {
return noRestraintRequest{}, false
}

12
pkg/util/flowcontrol/match_test.go
View File

@ -102,8 +102,8 @@ func TestLiterals(t *testing.T) {
Name: "eman",
Parts: []string{"goodrscs", "eman"},
},
User: ui,
Width: fcrequest.Width{Seats: 1},
User: ui,
WorkEstimate: fcrequest.WorkEstimate{Seats: 1},
}
reqRU := RequestDigest{
RequestInfo: &request.RequestInfo{
@ -118,8 +118,8 @@ func TestLiterals(t *testing.T) {
Name: "eman",
Parts: []string{"goodrscs", "eman"},
},
User: ui,
Width: fcrequest.Width{Seats: 1},
User: ui,
WorkEstimate: fcrequest.WorkEstimate{Seats: 1},
}
reqN := RequestDigest{
RequestInfo: &request.RequestInfo{
@ -127,8 +127,8 @@ func TestLiterals(t *testing.T) {
Path: "/openapi/v2",
Verb: "goodverb",
},
User: ui,
Width: fcrequest.Width{Seats: 1},
User: ui,
WorkEstimate: fcrequest.WorkEstimate{Seats: 1},
}
checkRules(t, true, reqRN, []flowcontrol.PolicyRulesWithSubjects{{
Subjects: []flowcontrol.Subject{{Kind: flowcontrol.SubjectKindUser,

22
pkg/util/flowcontrol/request/width.go
View File

@ -20,28 +20,28 @@ import (
"net/http"
)
type Width struct {
type WorkEstimate struct {
// Seats represents the number of seats associated with this request
Seats uint
}
// DefaultWidthEstimator returns returns '1' as the "width"
// of the given request.
// DefaultWorkEstimator returns estimation with default number of seats
// of 1.
//
// TODO: when we plumb in actual "width" handling for different
// TODO: when we plumb in actual work estimate handling for different
// type of request(s) this function will iterate through a chain
// of widthEstimator instance(s).
func DefaultWidthEstimator(_ *http.Request) Width {
return Width{
// of workEstimator instance(s).
func DefaultWorkEstimator(_ *http.Request) WorkEstimate {
return WorkEstimate{
Seats: 1,
}
}
// WidthEstimatorFunc returns the estimated "width" of a given request.
// WorkEstimatorFunc returns the estimated work of a given request.
// This function will be used by the Priority & Fairness filter to
// estimate the "width" of incoming requests.
type WidthEstimatorFunc func(*http.Request) Width
// estimate the work of of incoming requests.
type WorkEstimatorFunc func(*http.Request) WorkEstimate
func (e WidthEstimatorFunc) EstimateWidth(r *http.Request) Width {
func (e WorkEstimatorFunc) EstimateWork(r *http.Request) WorkEstimate {
return e(r)
}