##// END OF EJS Templates
nodemap: introduce an option to use mmap to read the nodemap mapping...
nodemap: introduce an option to use mmap to read the nodemap mapping The performance and memory benefit is much greater if we don't have to copy all the data in memory for each information. So we introduce an option (on by default) to read the data using mmap. This changeset is the last one definition the API for index support nodemap data. (they have to be able to use the mmaping). Below are some benchmark comparing the best we currently have in 5.3 with the final step of this series (using the persistent nodemap implementation in Rust). The benchmark run `hg perfindex` with various revset and the following variants: Before: * do not use the persistent nodemap * use the CPython implementation of the index for nodemap * use mmapping of the changelog index After: * use the MixedIndex Rust code, with the NodeTree object for nodemap access (still in review) * use the persistent nodemap data from disk * access the persistent nodemap data through mmap * use mmapping of the changelog index The persistent nodemap greatly speed up most operation on very large repositories. Some of the previously very fast lookup end up a bit slower because the persistent nodemap has to be setup. However the absolute slowdown is very small and won't matters in the big picture. Here are some numbers (in seconds) for the reference copy of mozilla-try: Revset Before After abs-change speedup -10000: 0.004622 0.005532 0.000910 × 0.83 -10: 0.000050 0.000132 0.000082 × 0.37 tip 0.000052 0.000085 0.000033 × 0.61 0 + (-10000:) 0.028222 0.005337 -0.022885 × 5.29 0 0.023521 0.000084 -0.023437 × 280.01 (-10000:) + 0 0.235539 0.005308 -0.230231 × 44.37 (-10:) + :9 0.232883 0.000180 -0.232703 ×1293.79 (-10000:) + (:99) 0.238735 0.005358 -0.233377 × 44.55 :99 + (-10000:) 0.317942 0.005593 -0.312349 × 56.84 :9 + (-10:) 0.313372 0.000179 -0.313193 ×1750.68 :9 0.316450 0.000143 -0.316307 ×2212.93 On smaller repositories, the cost of nodemap related operation is not as big, so the win is much more modest. Yet it helps shaving a handful of millisecond here and there. Here are some numbers (in seconds) for the reference copy of mercurial: Revset Before After abs-change speedup -10: 0.000065 0.000097 0.000032 × 0.67 tip 0.000063 0.000078 0.000015 × 0.80 0 0.000561 0.000079 -0.000482 × 7.10 -10000: 0.004609 0.003648 -0.000961 × 1.26 0 + (-10000:) 0.005023 0.003715 -0.001307 × 1.35 (-10:) + :9 0.002187 0.000108 -0.002079 ×20.25 (-10000:) + 0 0.006252 0.003716 -0.002536 × 1.68 (-10000:) + (:99) 0.006367 0.003707 -0.002660 × 1.71 :9 + (-10:) 0.003846 0.000110 -0.003736 ×34.96 :9 0.003854 0.000099 -0.003755 ×38.92 :99 + (-10000:) 0.007644 0.003778 -0.003866 × 2.02 Differential Revision: https://phab.mercurial-scm.org/D7894

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lib.rs
177 lines | 5.0 KiB | application/rls-services+xml | RustLexer
// 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 use ancestors::{AncestorsIterator, LazyAncestors, MissingAncestors};
mod dirstate;
pub mod discovery;
pub mod testing; // unconditionally built, for use from integration tests
pub use dirstate::{
dirs_multiset::{DirsMultiset, DirsMultisetIter},
dirstate_map::DirstateMap,
parsers::{pack_dirstate, parse_dirstate, PARENT_SIZE},
status::{status, StatusResult},
CopyMap, CopyMapIter, DirstateEntry, DirstateParents, EntryState,
StateMap, StateMapIter,
};
mod filepatterns;
pub mod matchers;
pub mod revlog;
pub use revlog::*;
#[cfg(feature = "with-re2")]
pub mod re2;
pub mod utils;
use crate::utils::hg_path::{HgPathBuf, HgPathError};
pub use filepatterns::{
parse_pattern_syntax, read_pattern_file, IgnorePattern,
PatternFileWarning, PatternSyntax,
};
use std::collections::HashMap;
use twox_hash::RandomXxHashBuilder64;
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(Clone, Debug, PartialEq)]
pub enum DirstateParseError {
TooLittleData,
Overflow,
CorruptedEntry(String),
Damaged,
}
impl From<std::io::Error> for DirstateParseError {
fn from(e: std::io::Error) -> Self {
DirstateParseError::CorruptedEntry(e.to_string())
}
}
impl ToString for DirstateParseError {
fn to_string(&self) -> String {
use crate::DirstateParseError::*;
match self {
TooLittleData => "Too little data for dirstate.".to_string(),
Overflow => "Overflow in dirstate.".to_string(),
CorruptedEntry(e) => format!("Corrupted entry: {:?}.", e),
Damaged => "Dirstate appears to be damaged.".to_string(),
}
}
}
#[derive(Debug, PartialEq)]
pub enum DirstatePackError {
CorruptedEntry(String),
CorruptedParent,
BadSize(usize, usize),
}
impl From<std::io::Error> for DirstatePackError {
fn from(e: std::io::Error) -> Self {
DirstatePackError::CorruptedEntry(e.to_string())
}
}
#[derive(Debug, PartialEq)]
pub enum DirstateMapError {
PathNotFound(HgPathBuf),
EmptyPath,
InvalidPath(HgPathError),
}
impl ToString for DirstateMapError {
fn to_string(&self) -> String {
match self {
DirstateMapError::PathNotFound(_) => {
"expected a value, found none".to_string()
}
DirstateMapError::EmptyPath => "Overflow in dirstate.".to_string(),
DirstateMapError::InvalidPath(e) => e.to_string(),
}
}
}
pub enum DirstateError {
Parse(DirstateParseError),
Pack(DirstatePackError),
Map(DirstateMapError),
IO(std::io::Error),
}
impl From<DirstateParseError> for DirstateError {
fn from(e: DirstateParseError) -> Self {
DirstateError::Parse(e)
}
}
impl From<DirstatePackError> for DirstateError {
fn from(e: DirstatePackError) -> Self {
DirstateError::Pack(e)
}
}
#[derive(Debug)]
pub enum PatternError {
Path(HgPathError),
UnsupportedSyntax(String),
UnsupportedSyntaxInFile(String, String, usize),
TooLong(usize),
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 ToString for PatternError {
fn to_string(&self) -> String {
match self {
PatternError::UnsupportedSyntax(syntax) => {
format!("Unsupported syntax {}", syntax)
}
PatternError::UnsupportedSyntaxInFile(syntax, file_path, line) => {
format!(
"{}:{}: unsupported syntax {}",
file_path, line, syntax
)
}
PatternError::TooLong(size) => {
format!("matcher pattern is too long ({} bytes)", size)
}
PatternError::IO(e) => e.to_string(),
PatternError::Path(e) => e.to_string(),
PatternError::NonRegexPattern(pattern) => {
format!("'{:?}' cannot be turned into a regex", pattern)
}
}
}
}
impl From<DirstateMapError> for DirstateError {
fn from(e: DirstateMapError) -> Self {
DirstateError::Map(e)
}
}
impl From<std::io::Error> for DirstateError {
fn from(e: std::io::Error) -> Self {
DirstateError::IO(e)
}
}
impl From<std::io::Error> for PatternError {
fn from(e: std::io::Error) -> Self {
PatternError::IO(e)
}
}
impl From<HgPathError> for PatternError {
fn from(e: HgPathError) -> Self {
PatternError::Path(e)
}
}