vmalert: always re-evaluate Annotations (#3119)

* vmalert: always re-evaluate Annotations

Previously, Annotations were evaluated only:
1. On alert creating.
2. On alert's value change.

This is premature optimization. It was assumed that since annotations
could contain only text with alert's labels or value - there is no need
in spending resources to re-compile Annotations.

Later, template function `query` was added, which can execute
arbitrary queries and return different results on every evaluation.
So if it was used in annotations, it would be executed only on init
or value change.

Another case when optimization caused an issue - annotations hot reload.
In this case, annotations of the active alert won't change even if Rule's
annotations were changed.

This fix enables Annotations re-evaluation on each iteration to resolve
issues above. It would have some impact on performance, but it is unlikely
it will be noticeable.

Signed-off-by: hagen1778 <roman@victoriametrics.com>

* vmalert: add tp Changelog

Signed-off-by: hagen1778 <roman@victoriametrics.com>

Signed-off-by: hagen1778 <roman@victoriametrics.com>
This commit is contained in:
Roman Khavronenko 2022-09-16 16:19:10 +02:00 committed by Aliaksandr Valialkin
parent 1c13cce5ed
commit 360b022603
No known key found for this signature in database
GPG key ID: A72BEC6CD3D0DED1
2 changed files with 6 additions and 10 deletions

View file

@ -324,16 +324,11 @@ func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]pr
a.ActiveAt = ts
ar.logDebugf(ts, a, "INACTIVE => PENDING")
}
if a.Value != m.Values[0] {
// update Value field with the latest value
a.Value = m.Values[0]
// and re-exec template since Value can be used
// in annotations
a.Annotations, err = a.ExecTemplate(qFn, ls.origin, ar.Annotations)
if err != nil {
curState.err = err
return nil, curState.err
}
a.Value = m.Values[0]
// re-exec template since Value or query can be used in annotations
a.Annotations, err = a.ExecTemplate(qFn, ls.origin, ar.Annotations)
if err != nil {
return nil, err
}
continue
}

View file

@ -31,6 +31,7 @@ The following tip changes can be tested by building VictoriaMetrics components f
* BUGFIX: [VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html): properly calculate query results at `vmselect`. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3067). The issue has been introduced in [v1.81.0](https://docs.victoriametrics.com/CHANGELOG.html#v1810).
* BUGFIX: [VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html): log clear error when multiple identical `-storageNode` command-line flags are passed to `vmselect` or to `vminsert`. Previously these components were crashed with cryptic panic `metric ... is already registered` in this case. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3076).
* BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): fix `RangeError: Maximum call stack size exceeded` error when the query returns too many data points at `Table` view. See [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/3092/files).
* BUGFIX: [vmalert](https://docs.victoriametrics.com/vmalert.html): re-evaluate alert's annotations on each execution. Previously, annotations were evaluated only on alert's value change. See [this PR](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/3119) for details.
## [v1.81.2](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.81.2)