llbsolver: create single temp lease for exports for performance #4947
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Outdated suggestions cannot be applied.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.
Currently there is a temp lease creation in
GetRemotes()
called from exporters, cache-exporting, and provenance creation and gets called for every cache result when walking the graph. 99% time it returns nil or reference to blob that already existed but temp lease is needed for the odd case where it needs to create new blobs to make sure the code does not go to race against containerd GC. Although it looks like creating a lease is justcontext.WithValue
it is actually quite expensive as it is written into containerd boltdb. This improves performance in this case by creating a single temp lease for the whole export phase of a single job so calls insideGetRemotes()
don't need to create their own one for safety.