| commit | 05d91c021babbfadfd7ad4d090d26c3dd7e37078 | |
| author | Michael Thomas <mjt@fb.com> | |
| Wed, 11 May 2022 17:47:48 +0000 (11 10:47 -0700) | ||
| committer | Facebook GitHub Bot <facebook-github-bot@users.noreply.github.com> | |
| Wed, 11 May 2022 17:47:48 +0000 (11 10:47 -0700) | ||
| tree | 3a16e058e53a8110e0af6308f8267595ce007443 | treesnapshot (tar.gz zip) |
| parent | 158d256c7ae50c527298197458769d430ccf4b0f | commitdiff |
Avoid quadratic slowdown in markdown rendering
Summary:
The `markdown_lite` parser is using left-associated list append; since the left hand operand is itself the result of a list append, we end up traversing it again and end up with a quadratic slowdown. In pathological cases in the linked tasks, where we have shapes with over 4000 fields(!), this brings rendering to a grinding halt.
This diff replaces append with cons & rev.
Reviewed By: Wilfred, hgoldstein
Differential Revision: D36314037
fbshipit-source-id: ce7f58f9f34292bd2c9bdbcc354edf8416cfca3f
Summary:
The `markdown_lite` parser is using left-associated list append; since the left hand operand is itself the result of a list append, we end up traversing it again and end up with a quadratic slowdown. In pathological cases in the linked tasks, where we have shapes with over 4000 fields(!), this brings rendering to a grinding halt.
This diff replaces append with cons & rev.
Reviewed By: Wilfred, hgoldstein
Differential Revision: D36314037
fbshipit-source-id: ce7f58f9f34292bd2c9bdbcc354edf8416cfca3f
| hphp/hack/src/errors/markdown_lite.ml | diffblobblamehistory |