##// END OF EJS Templates
dirstate-tree: Avoid BTreeMap double-lookup when inserting a dirstate entry...
dirstate-tree: Avoid BTreeMap double-lookup when inserting a dirstate entry The child nodes of a given node in the tree-shaped dirstate are kept in a `BTreeMap` where keys are file names as strings. Finding or inserting a value in the map takes `O(log(n))` string comparisons, which adds up when constructing the tree. The `entry` API allows finding a "spot" in the map that may or may not be occupied and then access that value or insert a new one without doing map lookup again. However the current API is limited in that calling `entry` requires an owned key (and so a memory allocation), even if it ends up not being used in the case where the map already has a value with an equal key. This is still a win, with 4% better end-to-end time for `hg status` measured here with hyperfine: ``` Benchmark #1: ../hg2/hg status -R $REPO --config=experimental.dirstate-tree.in-memory=1 Time (mean ± σ): 1.337 s ± 0.018 s [User: 892.9 ms, System: 437.5 ms] Range (min … max): 1.316 s … 1.373 s 10 runs Benchmark #2: ./hg status -R $REPO --config=experimental.dirstate-tree.in-memory=1 Time (mean ± σ): 1.291 s ± 0.008 s [User: 853.4 ms, System: 431.1 ms] Range (min … max): 1.283 s … 1.309 s 10 runs Summary './hg status -R $REPO --config=experimental.dirstate-tree.in-memory=1' ran 1.04 ± 0.02 times faster than '../hg2/hg status -R $REPO --config=experimental.dirstate-tree.in-memory=1' ``` * ./hg is this revision * ../hg2/hg is its parent * $REPO is an old snapshot of mozilla-central Differential Revision: https://phab.mercurial-scm.org/D10550

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main.rs
39 lines | 1.4 KiB | application/rls-services+xml | RustLexer
use pyembed::MainPythonInterpreter;
// Include an auto-generated file containing the default
// `pyembed::PythonConfig` derived by the PyOxidizer configuration file.
//
// If you do not want to use PyOxidizer to generate this file, simply
// remove this line and instantiate your own instance of
// `pyembed::PythonConfig`.
include!(env!("PYOXIDIZER_DEFAULT_PYTHON_CONFIG_RS"));
fn main() {
// The following code is in a block so the MainPythonInterpreter is
// destroyed in an orderly manner, before process exit.
let code = {
// Load the default Python configuration as derived by the PyOxidizer
// config file used at build time.
let config = default_python_config();
// Construct a new Python interpreter using that config, handling any
// errors from construction.
match MainPythonInterpreter::new(config) {
Ok(mut interp) => {
// And run it using the default run configuration as specified
// by the configuration. If an uncaught Python
// exception is raised, handle it.
// This includes the special SystemExit, which is a request to
// terminate the process.
interp.run_as_main()
}
Err(msg) => {
eprintln!("{}", msg);
1
}
}
};
// And exit the process according to code execution results.
std::process::exit(code);
}