From b09c6d56832eb1718c07d74abf3bc6ae3fe4e030 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 14:36:04 +0200 Subject: Adding upstream version 1.1.0. Signed-off-by: Daniel Baumann --- pkg/backoff/backoff.go | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 pkg/backoff/backoff.go (limited to 'pkg/backoff/backoff.go') diff --git a/pkg/backoff/backoff.go b/pkg/backoff/backoff.go new file mode 100644 index 0000000..6ce7bee --- /dev/null +++ b/pkg/backoff/backoff.go @@ -0,0 +1,43 @@ +package backoff + +import ( + "math/rand" + "time" +) + +// Backoff returns the backoff duration for a specific retry attempt. +type Backoff func(uint64) time.Duration + +// NewExponentialWithJitter returns a backoff implementation that +// exponentially increases the backoff duration for each retry from min, +// never exceeding max. Some randomization is added to the backoff duration. +// It panics if min >= max. +func NewExponentialWithJitter(min, max time.Duration) Backoff { + if min <= 0 { + min = time.Millisecond * 100 + } + if max <= 0 { + max = time.Second * 10 + } + if min >= max { + panic("max must be larger than min") + } + + return func(attempt uint64) time.Duration { + e := min << attempt + if e <= 0 || e > max { + e = max + } + + return time.Duration(jitter(int64(e))) + } +} + +// jitter returns a random integer distributed in the range [n/2..n). +func jitter(n int64) int64 { + if n == 0 { + return 0 + } + + return n/2 + rand.Int63n(n/2) +} -- cgit v1.2.3