cd99ccc1de
Signed-off-by: Aoi K <koizumi.aoi@chaotic.ninja> git-svn-id: file:///srv/svn/repo/suika/trunk@804 f0ae65fe-ee39-954e-97ec-027ff2717ef4
41 lines
604 B
Go
41 lines
604 B
Go
package suika
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import (
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"math/rand"
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"time"
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)
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// backoffer implements a simple exponential backoff.
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type backoffer struct {
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min, max, jitter time.Duration
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n int64
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}
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func newBackoffer(min, max, jitter time.Duration) *backoffer {
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return &backoffer{min: min, max: max, jitter: jitter}
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}
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func (b *backoffer) Reset() {
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b.n = 0
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}
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func (b *backoffer) Next() time.Duration {
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if b.n == 0 {
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b.n = 1
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return 0
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}
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d := time.Duration(b.n) * b.min
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if d > b.max {
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d = b.max
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} else {
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b.n *= 2
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}
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if b.jitter != 0 {
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d += time.Duration(rand.Int63n(int64(b.jitter)))
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}
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return d
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}
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