fix: out of memory issue due to accumulation of items in ScanContext
#103
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Outdated suggestions cannot be applied.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.
ScanContext
contains hash maps that tracks the matches found for each pattern. The values in these maps are vectors that can become very large. For performance reasons, instead of completely deallocating those vectors after each scan, we were clearing the vector but retaining its capacity, so that they can be reused in later scans. The problem with that is that these vectors are not freed while the scanner is in use, and this can have a large impact on the process' memory footprint, causing OOM issues.This PR adds a
PatternMatches
type that encapsulates all the logic for tracking pattern matches, including a more sophisticated approach that tries to reuse the vectors as much as possible, but frees them when they grow too much.