Mercurial > hg
changeset 44779:b15a37d85dbe stable
rust-regex: increase the DFA size limit for the `regex` crate
`re2`'s DFA limit is already increased in `rust/hg-core/src/re2/rust_re2.cpp`,
the same has to be done for the `regex` crate.
Big repositories with big `.hgignore`s will sometimes hit this limit and face
extreme performance regressions (I've seen one take *minutes* for `hg status`).
Differential Revision: https://phab.mercurial-scm.org/D8499
| author | Raphaël Gomès <rgomes@octobus.net> |
|---|---|
| date | Thu, 07 May 2020 10:15:19 +0200 |
| parents | ee0790b67c45 |
| children | f727939f3513 |
| files | rust/hg-core/src/matchers.rs |
| diffstat | 1 files changed, 4 insertions(+), 0 deletions(-) [+] |
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--- a/rust/hg-core/src/matchers.rs Fri May 01 21:47:39 2020 +0530 +++ b/rust/hg-core/src/matchers.rs Thu May 07 10:15:19 2020 +0200 @@ -358,6 +358,10 @@ let pattern_string = unsafe { String::from_utf8_unchecked(escaped_bytes) }; let re = regex::bytes::RegexBuilder::new(&pattern_string) .unicode(false) + // Big repos with big `.hgignore` will hit the default limit and + // incur a significant performance hit. One repo's `hg status` hit + // multiple *minutes*. + .dfa_size_limit(50 * (1 << 20)) .build() .map_err(|e| PatternError::UnsupportedSyntax(e.to_string()))?;