Don't write empty values to the index. #2557
Merged
Conversation
This file contains hidden or 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
This causes tombstones to be written to Cassandra, which causes excessive heap usage.: Signed-off-by: Tom Wilkie <tom@grafana.com>
gouthamve
approved these changes
May 5, 2020
gouthamve
pushed a commit
to grafana/cortex
that referenced
this pull request
May 7, 2020
This causes tombstones to be written to Cassandra, which causes excessive heap usage.: Signed-off-by: Tom Wilkie <tom@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Outdated suggestions cannot be applied.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.
This causes tombstones to be written to Cassandra, which causes excessive heap usage.:
Signed-off-by: Tom Wilkie tom@grafana.com
What this PR does:
We write empty values (just using the row and column value) for metric name and series rows.
These empty value cause tombstones to be written to Cortex (https://thelastpickle.com/blog/2018/07/05/undetectable-tombstones-in-apache-cassandra.html). Tombstones make Cassandra slow(er).
Checklist
CHANGELOG.mdupdated - the order of entries should be[CHANGE],[FEATURE],[ENHANCEMENT],[BUGFIX]