diff options
author | HuabingZhao <zhao.huabing@zte.com.cn> | 2017-09-04 19:33:48 +0800 |
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committer | HuabingZhao <zhao.huabing@zte.com.cn> | 2017-09-04 19:34:03 +0800 |
commit | c4a34b2fe6f7317bf17fa478a734e5bdab30c278 (patch) | |
tree | 8b65034b069a657f2531137b389a0c1d4919b79a /src/kube2msb/vendor/k8s.io/kubernetes/pkg/util/flowcontrol/throttle.go | |
parent | cc0c6e3ed8fc6c9fd96ef843b866070f52537185 (diff) |
Use maven to build kube2msb
Issue-Id: OOM-61
Change-Id: Ic7e733c95e28b75b66535b343ae22c893db24531
Signed-off-by: HuabingZhao <zhao.huabing@zte.com.cn>
Diffstat (limited to 'src/kube2msb/vendor/k8s.io/kubernetes/pkg/util/flowcontrol/throttle.go')
-rw-r--r-- | src/kube2msb/vendor/k8s.io/kubernetes/pkg/util/flowcontrol/throttle.go | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/src/kube2msb/vendor/k8s.io/kubernetes/pkg/util/flowcontrol/throttle.go b/src/kube2msb/vendor/k8s.io/kubernetes/pkg/util/flowcontrol/throttle.go new file mode 100644 index 0000000..482ba7d --- /dev/null +++ b/src/kube2msb/vendor/k8s.io/kubernetes/pkg/util/flowcontrol/throttle.go @@ -0,0 +1,116 @@ +/* +Copyright 2014 The Kubernetes Authors. + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +*/ + +package flowcontrol + +import ( + "sync" + + "github.com/juju/ratelimit" +) + +type RateLimiter interface { + // TryAccept returns true if a token is taken immediately. Otherwise, + // it returns false. + TryAccept() bool + // Accept returns once a token becomes available. + Accept() + // Stop stops the rate limiter, subsequent calls to CanAccept will return false + Stop() + // Saturation returns a percentage number which describes how saturated + // this rate limiter is. + // Usually we use token bucket rate limiter. In that case, + // 1.0 means no tokens are available; 0.0 means we have a full bucket of tokens to use. + Saturation() float64 +} + +type tokenBucketRateLimiter struct { + limiter *ratelimit.Bucket +} + +// NewTokenBucketRateLimiter creates a rate limiter which implements a token bucket approach. +// The rate limiter allows bursts of up to 'burst' to exceed the QPS, while still maintaining a +// smoothed qps rate of 'qps'. +// The bucket is initially filled with 'burst' tokens, and refills at a rate of 'qps'. +// The maximum number of tokens in the bucket is capped at 'burst'. +func NewTokenBucketRateLimiter(qps float32, burst int) RateLimiter { + limiter := ratelimit.NewBucketWithRate(float64(qps), int64(burst)) + return &tokenBucketRateLimiter{limiter} +} + +func (t *tokenBucketRateLimiter) TryAccept() bool { + return t.limiter.TakeAvailable(1) == 1 +} + +func (t *tokenBucketRateLimiter) Saturation() float64 { + capacity := t.limiter.Capacity() + avail := t.limiter.Available() + return float64(capacity-avail) / float64(capacity) +} + +// Accept will block until a token becomes available +func (t *tokenBucketRateLimiter) Accept() { + t.limiter.Wait(1) +} + +func (t *tokenBucketRateLimiter) Stop() { +} + +type fakeAlwaysRateLimiter struct{} + +func NewFakeAlwaysRateLimiter() RateLimiter { + return &fakeAlwaysRateLimiter{} +} + +func (t *fakeAlwaysRateLimiter) TryAccept() bool { + return true +} + +func (t *fakeAlwaysRateLimiter) Saturation() float64 { + return 0 +} + +func (t *fakeAlwaysRateLimiter) Stop() {} + +func (t *fakeAlwaysRateLimiter) Accept() {} + +type fakeNeverRateLimiter struct { + wg sync.WaitGroup +} + +func NewFakeNeverRateLimiter() RateLimiter { + wg := sync.WaitGroup{} + wg.Add(1) + return &fakeNeverRateLimiter{ + wg: wg, + } +} + +func (t *fakeNeverRateLimiter) TryAccept() bool { + return false +} + +func (t *fakeNeverRateLimiter) Saturation() float64 { + return 1 +} + +func (t *fakeNeverRateLimiter) Stop() { + t.wg.Done() +} + +func (t *fakeNeverRateLimiter) Accept() { + t.wg.Wait() +} |