Memcached: Fix issue where non-zero TTLs were trunctated to zero #530
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Fixes an issue where if a non-zero TTL smaller than a full second was passed to the `SetAsync` or `SetMultiAsync` methods, the TTL would be truncated to zero seconds which results in the item being cached forever. Specifically, this fixes an issue in Mimir where items that were supposed to have a several minute TTL computed as `$start - $desired_ttl` ended up being cached forever. They were never evicted by Memcached because there was no need to free space in this particular cache due to low usage. Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>
56quarters
force-pushed
the
56quarters/memcached-zero-ttl
branch
from
9388145 to
6628102
Compare
chencs
approved these changes
Jun 11, 2024
56quarters
added a commit
to grafana/mimir
that referenced
this pull request
Jun 11, 2024
Specifically, pulls in grafana/dskit#530 to fix an issue where we may inadvertently cache things forever. Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>
4 tasks
56quarters
added a commit
to grafana/mimir
that referenced
this pull request
Jun 11, 2024
Specifically, pulls in grafana/dskit#530 to fix an issue where we may inadvertently cache things forever. Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>
56quarters
added a commit
to grafana/mimir
that referenced
this pull request
Jun 11, 2024
Specifically, pulls in grafana/dskit#530 to fix an issue where we may inadvertently cache things forever. Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
What this PR does:
Fixes an issue where if a non-zero TTL smaller than a full second was passed to the
SetAsyncorSetMultiAsyncmethods, the TTL would be truncated to zero seconds which results in the item being cached forever.Specifically, this fixes an issue in Mimir where items that were supposed to have a several minute TTL computed as
$ttl - time.Since($start)ended up being cached forever. They were never evicted by Memcached because there was no need to free space in this particular cache due to low usage.Which issue(s) this PR fixes:
Internal postmortem
Checklist
CHANGELOG.mdupdated - the order of entries should be[CHANGE],[FEATURE],[ENHANCEMENT],[BUGFIX]