comparison rust/hg-core/src/dirstate_tree/status.rs @ 50321:14b57943ae6d stable

rust: fix thread cap (for real this time)

Both e2f8ed37201c and c52435820bbd failed to put a *default* ceiling on
the number of threads used by Rayon to prevent a contention issue.

Calling `rayon::available_parallelism()` creates the global threadpool,
which made our whole dance useless last time.

50320:9c5e743e400c

    root_dir: PathBuf,
    ignore_files: Vec<PathBuf>,
    options: StatusOptions,
) -> Result<(DirstateStatus<'dirstate>, Vec<PatternFileWarning>), StatusError>
{
    // Force the global rayon threadpool to not exceed 16 concurrent threads.
    // This is a stop-gap measure until we figure out why using more than 16
    // threads makes `status` slower for each additional thread.
    // We use `ok()` in case the global threadpool has already been
    // instantiated in `rhg` or some other caller.
    // TODO find the underlying cause and fix it, then remove this.
    rayon::ThreadPoolBuilder::new()
        .num_threads(16.min(rayon::current_num_threads()))
        .build_global()
        .ok();

    let (ignore_fn, warnings, patterns_changed): (IgnoreFnType, _, _) =
        if options.list_ignored || options.list_unknown {
            let (ignore_fn, warnings, changed) = match dmap.dirstate_version {
                DirstateVersion::V1 => {

50321:14b57943ae6d

    root_dir: PathBuf,
    ignore_files: Vec<PathBuf>,
    options: StatusOptions,
) -> Result<(DirstateStatus<'dirstate>, Vec<PatternFileWarning>), StatusError>
{
    // Also cap for a Python caller of this function, but don't complain if
    // the global threadpool has already been set since this code path is also
    // being used by `rhg`, which calls this early.
    let _ = crate::utils::cap_default_rayon_threads();

    let (ignore_fn, warnings, patterns_changed): (IgnoreFnType, _, _) =
        if options.list_ignored || options.list_unknown {
            let (ignore_fn, warnings, changed) = match dmap.dirstate_version {
                DirstateVersion::V1 => {