Improve sparse file handling performance #715
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
Previously, sparse files were processed recursively. On highly fragmented files, this led to deep recursion and significant inefficiency. This change replaces the recursive approach with an iterative strategy, which scales better for files with many fragments. It also introduces generated tests that simulate sparse files with very high fragmentation to ensure correctness and performance under stress.
There was a problem hiding this comment.
Pull Request Overview
This PR improves sparse file handling performance by replacing a recursive approach with an iterative strategy that scales better for highly fragmented files. The change also introduces comprehensive test coverage to ensure correctness and performance under stress conditions with maximally fragmented sparse files.
Key changes:
- Replaced recursive sparse file processing with iterative
ComposedTarInputStream - Added comprehensive test suite with generated maximally fragmented sparse files
- Improved error handling with more specific
EOFExceptionmessages
Reviewed Changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.
Show a summary per file
| File | Description |
|---|---|
TarArchiveInputStreamTest.java |
Updated exception assertions from ArchiveException to EOFException |
SparseFilesTest.java |
Added parameterized tests for maximally fragmented sparse files |
TestArchiveGenerator.java |
New utility class to generate sparse file test cases |
BoundedArchiveInputStream.java |
Added input validation and improved documentation |
ArchiveUtils.java |
Added checkFromIndexSize utility method for array bounds checking |
TarFile.java |
Refactored sparse file handling to use ComposedTarInputStream |
TarArchiveInputStream.java |
Replaced recursive sparse reading with iterative approach |
ComposedTarInputStream.java |
New class implementing iterative sparse file reading |
Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.
src/test/java/org/apache/commons/compress/archivers/TestArchiveGenerator.java
Show resolved
Hide resolved
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.
Previously, sparse files were processed recursively. On highly fragmented files, this led to deep recursion and significant inefficiency.
This change replaces the recursive approach with an iterative strategy, which scales better for files with many fragments. It also introduces generated tests that simulate sparse files with very high fragmentation to ensure correctness and performance under stress.