Mercurial > public > mercurial-scm > hg
view rust/hg-core/src/lib.rs @ 48178:f12a19d03d2c
fix: reduce number of tool executions
By grouping together (path, ctx) pairs according to the inputs they would
provide to fixer tools, we can deduplicate executions of fixer tools to
significantly reduce the amount of time spent running slow tools.
This change does not handle clean files in the working copy, which could still
be deduplicated against the files in the checked out commit. It's a little
harder to do that because the filerev is not available in the workingfilectx
(and it doesn't exist for added files).
Anecdotally, this change makes some real uses cases at Google 10x faster. I
think we were originally hesitant to do this because the benefits weren't
obvious, and implementing it efficiently is kind of tricky. If we simply
memoized the formatter execution function, we would be keeping tons of file
content in memory.
Also included is a regression test for a corner case that I broke with my first
attempt at optimizing this code.
Differential Revision: https://phab.mercurial-scm.org/D11280
author | Danny Hooper <hooper@google.com> |
---|---|
date | Thu, 02 Sep 2021 14:08:45 -0700 |
parents | bf8837e3d7ce |
children | 5734b03ecf3e |
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// Copyright 2018-2020 Georges Racinet <georges.racinet@octobus.net> // and Mercurial contributors // // This software may be used and distributed according to the terms of the // GNU General Public License version 2 or any later version. mod ancestors; pub mod dagops; pub mod errors; pub use ancestors::{AncestorsIterator, LazyAncestors, MissingAncestors}; pub mod dirstate; pub mod dirstate_tree; pub mod discovery; pub mod exit_codes; pub mod requirements; pub mod testing; // unconditionally built, for use from integration tests pub use dirstate::{ dirs_multiset::{DirsMultiset, DirsMultisetIter}, status::{ BadMatch, BadType, DirstateStatus, HgPathCow, StatusError, StatusOptions, }, DirstateEntry, DirstateParents, EntryState, }; pub mod copy_tracing; mod filepatterns; pub mod matchers; pub mod repo; pub mod revlog; pub use revlog::*; pub mod config; pub mod logging; pub mod operations; pub mod revset; pub mod utils; pub mod vfs; use crate::utils::hg_path::{HgPathBuf, HgPathError}; pub use filepatterns::{ parse_pattern_syntax, read_pattern_file, IgnorePattern, PatternFileWarning, PatternSyntax, }; use std::collections::HashMap; use std::fmt; use twox_hash::RandomXxHashBuilder64; /// This is a contract between the `micro-timer` crate and us, to expose /// the `log` crate as `crate::log`. use log; pub type LineNumber = usize; /// Rust's default hasher is too slow because it tries to prevent collision /// attacks. We are not concerned about those: if an ill-minded person has /// write access to your repository, you have other issues. pub type FastHashMap<K, V> = HashMap<K, V, RandomXxHashBuilder64>; #[derive(Debug, PartialEq)] pub enum DirstateMapError { PathNotFound(HgPathBuf), EmptyPath, InvalidPath(HgPathError), } impl fmt::Display for DirstateMapError { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { match self { DirstateMapError::PathNotFound(_) => { f.write_str("expected a value, found none") } DirstateMapError::EmptyPath => { f.write_str("Overflow in dirstate.") } DirstateMapError::InvalidPath(path_error) => path_error.fmt(f), } } } #[derive(Debug, derive_more::From)] pub enum DirstateError { Map(DirstateMapError), Common(errors::HgError), } impl fmt::Display for DirstateError { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { match self { DirstateError::Map(error) => error.fmt(f), DirstateError::Common(error) => error.fmt(f), } } } #[derive(Debug, derive_more::From)] pub enum PatternError { #[from] Path(HgPathError), UnsupportedSyntax(String), UnsupportedSyntaxInFile(String, String, usize), TooLong(usize), #[from] IO(std::io::Error), /// Needed a pattern that can be turned into a regex but got one that /// can't. This should only happen through programmer error. NonRegexPattern(IgnorePattern), } impl fmt::Display for PatternError { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { match self { PatternError::UnsupportedSyntax(syntax) => { write!(f, "Unsupported syntax {}", syntax) } PatternError::UnsupportedSyntaxInFile(syntax, file_path, line) => { write!( f, "{}:{}: unsupported syntax {}", file_path, line, syntax ) } PatternError::TooLong(size) => { write!(f, "matcher pattern is too long ({} bytes)", size) } PatternError::IO(error) => error.fmt(f), PatternError::Path(error) => error.fmt(f), PatternError::NonRegexPattern(pattern) => { write!(f, "'{:?}' cannot be turned into a regex", pattern) } } } }