mudhorn/prometheus
1
0
Fork 0
mirror of https://github.com/prometheus/prometheus.git synced 2024-11-09 23:24:05 -08:00
Code Issues Actions 3 Packages Projects Releases Wiki Activity

tsdb: comment reason for isolation tracking reads (#11301)

Browse source 
I find it useful to know why a restriction exists, to check whether that
reason still applies, or in which other places it might apply.

This is based on the note here:
https://github.com/prometheus/prometheus/pull/9270#pullrequestreview-743820956
on the PR where the original comment was added.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
This commit is contained in:
Bryan Boreham 2022-09-13 10:11:03 +01:00 committed by GitHub
parent 770014e6f4
commit 136f8b0ebb
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
1 changed files with 2 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
tsdb/isolation.go
View file

@ -122,7 +122,8 @@ func (i *isolation) State(mint, maxt int64) *isolationState {
i.appendMtx.RLock() // Take append mutex before read mutex.
defer i.appendMtx.RUnlock()
// We need to track the reads even when isolation is disabled.
// We need to track reads even when isolation is disabled, so that head
// truncation can wait till reads overlapping that range have finished.
isoState := &isolationState{
maxAppendID: i.appendsOpenList.appendID,
lowWatermark: i.appendsOpenList.next.appendID, // Lowest appendID from appenders, or lastAppendId.