Shard parquet files based on configured number of columns limit#131
Open
yeya24 wants to merge 3 commits intoprometheus-community:mainfrom
Open
Shard parquet files based on configured number of columns limit#131yeya24 wants to merge 3 commits intoprometheus-community:mainfrom
yeya24 wants to merge 3 commits intoprometheus-community:mainfrom
Conversation
Signed-off-by: yeya24 <benye@amazon.com>
Signed-off-by: yeya24 <benye@amazon.com>
yeya24
force-pushed
the
shard-conversion-column-limit
branch
from
da336a1 to
0d469a3
Compare
Signed-off-by: yeya24 <benye@amazon.com>
MichaHoffmann
approved these changes
Jan 20, 2026
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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 PR introduces an automatic parquet file sharding based on the limit of number of columns in the generated parquet file. The parquet go library has a max limit of 32767 columns so this PR tries to shard based on that whenever number of columns would exceed the limit.
The implementation is using the same approach as thanos-io/thanos-parquet-gateway#34 to use a map to keep track of number of labels and split whenever reaching limit.
It tries to handle both sharded reader and single reader path. We used to not shard at all in the single reader scenario but if it identifies that there are more label names than the configured limit, it tries to use the same code path to shard blocks.