Use an LRU cache for indexes #1768
Open
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
For the index cache (which is always global currently), we don't set an upper bound as to how many indexes can be cached. That's likely benign in local cases but causes an arbitray amount of memory to be consumed if used as a service. This introduces an LRU cache instead, which can be configured using APKO_INDEX_CACHE_SIZE. I think this also fixes a race in the existing implementation where we'd leak indexes with outdated etags if two HEAD requests would race outside of the critical section of adjusting the etag pointers.
markusthoemmes
force-pushed
the
lru-cache
branch
from
0ca41c1 to
1b58f99
Compare
jonjohnsonjr
approved these changes
Jul 18, 2025
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Outdated suggestions cannot be applied.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.
For the index cache (which is always global currently), we don't set an upper bound as to how many indexes can be cached. That's likely benign in local cases but causes an arbitray amount of memory to be consumed if used as a service. This introduces an LRU cache instead, which can be configured using APKO_INDEX_CACHE_SIZE.
I think this also fixes a race in the existing implementation where we'd leak indexes with outdated etags if two HEAD requests would race outside of the critical section of adjusting the etag pointers.