VictoriaMetrics/app/vmctl/backoff/backoff.go
Dmytro Kozlov 6f401daacb
vmctl: add --backoff-retries, --backoff-factor, --backoff-min-duration global command-line flags (#6639)
### Describe Your Changes

Added `--vm-backoff-retries`, `--vm-backoff-factor`,
`--vm-backoff-min-duration` and `--vm-native-backoff-retries`,
`--vm-native-backoff-factor`, `--vm-native-backoff-min-duration`
command-line flags to the `vmctl` app. Those changes will help to
configure the retry backoff policy for different situations.

Related issue:
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6622
### Checklist

The following checks are **mandatory**:

- [X] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).

---------

Signed-off-by: hagen1778 <roman@victoriametrics.com>
Co-authored-by: hagen1778 <roman@victoriametrics.com>
2024-08-03 19:12:48 +02:00

77 lines
1.9 KiB
Go

package backoff
import (
"context"
"errors"
"fmt"
"math"
"time"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
)
// retryableFunc describes call back which will repeat on errors
type retryableFunc func() error
// ErrBadRequest is an error returned on bad request
var ErrBadRequest = errors.New("bad request")
// Backoff describes object with backoff policy params
type Backoff struct {
retries int
factor float64
minDuration time.Duration
}
// New initialize backoff object
func New(retries int, factor float64, minDuration time.Duration) (*Backoff, error) {
if retries <= 0 {
return nil, fmt.Errorf("number of backoff retries must be greater than 0")
}
if factor <= 1 {
return nil, fmt.Errorf("backoff retry factor must be greater than 1")
}
if minDuration <= 0 {
return nil, fmt.Errorf("backoff retry minimum duration must be greater than 0")
}
return &Backoff{
retries: retries,
factor: factor,
minDuration: minDuration,
}, nil
}
// Retry process retries until all attempts are completed
func (b *Backoff) Retry(ctx context.Context, cb retryableFunc) (uint64, error) {
var attempt uint64
for i := 0; i < b.retries; i++ {
err := cb()
if err == nil {
return attempt, nil
}
if errors.Is(err, ErrBadRequest) || errors.Is(err, context.Canceled) {
logger.Errorf("unrecoverable error: %s", err)
return attempt, err // fail fast if not recoverable
}
attempt++
backoff := float64(b.minDuration) * math.Pow(b.factor, float64(i))
dur := time.Duration(backoff)
logger.Errorf("got error: %s on attempt: %d; will retry in %v", err, attempt, dur)
t := time.NewTimer(dur)
select {
case <-t.C:
// duration elapsed, loop
case <-ctx.Done():
// context cancelled, kill the timer if it hasn't fired, and return
// the last error we got
if !t.Stop() {
<-t.C
}
return attempt, err
}
}
return attempt, fmt.Errorf("execution failed after %d retry attempts", b.retries)
}