Skip to content

Revert "Change Brotli CompressionLevel.Fastest to use quality 2 instead of 1"#120733

Merged
rzikm merged 1 commit intomainfrom
revert-120433-copilot/fix-af986064-2b8a-446b-8c11-7a5b8f412b6b
Oct 15, 2025
Merged

Revert "Change Brotli CompressionLevel.Fastest to use quality 2 instead of 1"#120733
rzikm merged 1 commit intomainfrom
revert-120433-copilot/fix-af986064-2b8a-446b-8c11-7a5b8f412b6b

Conversation

@rzikm
Copy link
Member

@rzikm rzikm commented Oct 15, 2025

Reverts #120433
Closes #120711

Unfortunately, increasing the quality decreases performance when batching the input (as is the expected usage). And the large (in some benchmarks up to 80% slowdown) performance hit does not justify fixing the small writes scenario this way.

Copilot AI review requested due to automatic review settings October 15, 2025 07:17
Copy link
Contributor

Copilot AI left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Pull Request Overview

This PR reverts a previous change that increased the Brotli compression quality for CompressionLevel.Fastest from 1 to 2. The revert is necessary because the quality increase caused significant performance degradation (up to 80% slowdown in some benchmarks) when batching input, which is the expected usage pattern.

Key Changes

  • Reverts Brotli CompressionLevel.Fastest quality from 2 back to 1
  • Removes comment explaining the rationale for using quality 2
  • Restores original performance characteristics for batched compression scenarios

@dotnet-policy-service
Copy link
Contributor

Tagging subscribers to this area: @dotnet/area-system-io-compression
See info in area-owners.md if you want to be subscribed.

@rzikm rzikm merged commit 6d1f810 into main Oct 15, 2025
84 of 86 checks passed
@stephentoub stephentoub deleted the revert-120433-copilot/fix-af986064-2b8a-446b-8c11-7a5b8f412b6b branch October 17, 2025 12:47
@github-actions github-actions bot locked and limited conversation to collaborators Nov 17, 2025
Sign up for free to subscribe to this conversation on GitHub. Already have an account? Sign in.

Projects

None yet

Development

Successfully merging this pull request may close these issues.

[Perf] Linux/x64: 3 Regressions on 10/10/2025 11:27:19 AM +00:00

3 participants