Avoid unnecessary stores in readVarint on AArch64 #677
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
Instead of storing result to memory at each byte iteration, we can keep temp result in a register and only write to memory once at the end. This reduces unnecessary memory stores and improves performance. Benchmark result without this patch: ============================================================================ [...]hrift/lib/cpp2/test/ProtocolBench.cpp relative time/iter iters/s ============================================================================ CompactProtocol_read_BigListBigInt 34.46us 29.02K Benchmark result with this patch: ============================================================================ [...]hrift/lib/cpp2/test/ProtocolBench.cpp relative time/iter iters/s ============================================================================ CompactProtocol_read_BigListBigInt 30.21us 33.10K Performance is uplifted by 14%.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
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Outdated suggestions cannot be applied.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.
Instead of storing result to memory at each byte iteration, we can keep temp result in a register and only write to memory once at the end. This reduces unnecessary memory stores and improves performance.
Benchmark result without this patch:
[...]hrift/lib/cpp2/test/ProtocolBench.cpp relative time/iter iters/s
CompactProtocol_read_BigListBigInt 34.46us 29.02K
Benchmark result with this patch:
[...]hrift/lib/cpp2/test/ProtocolBench.cpp relative time/iter iters/s
CompactProtocol_read_BigListBigInt 30.21us 33.10K
Performance is uplifted by 14%.