Create worker threads only once (for performance)

This improves performance by a factor of at least 2 in large --tree workloads by avoiding the repeated creation/destruction of the pool and containing threads.
Cycling pools also encountered lots lock contention, which accounted for most of the time saved by reusing a single pool.
This commit is contained in:
Alexandru Macovei 2018-02-14 03:53:53 +02:00
parent 0eb7966294
commit 8cbde76b4c

View File

@ -77,6 +77,7 @@ use output::cell::TextCell;
use output::tree::{TreeTrunk, TreeParams, TreeDepth};
use output::file_name::FileStyle;
use output::table::{Table, Options as TableOptions, Row as TableRow};
use scoped_threadpool::Pool;
/// With the **Details** view, the output gets formatted into columns, with
@ -142,6 +143,8 @@ impl<'a> AsRef<File<'a>> for Egg<'a> {
impl<'a> Render<'a> {
pub fn render<W: Write>(self, mut git: Option<&'a GitCache>, ignore: Option<&'a IgnoreCache>, w: &mut W) -> IOResult<()> {
use num_cpus;
let mut pool = Pool::new(num_cpus::get() as u32);
let mut rows = Vec::new();
if let Some(ref table) = self.opts.table {
@ -162,14 +165,14 @@ impl<'a> Render<'a> {
// This is weird, but I cant find a way around it:
// https://internals.rust-lang.org/t/should-option-mut-t-implement-copy/3715/6
let mut table = Some(table);
self.add_files_to_table(&mut table, &mut rows, &self.files, ignore, TreeDepth::root());
self.add_files_to_table(&mut pool, &mut table, &mut rows, &self.files, ignore, TreeDepth::root());
for row in self.iterate_with_table(table.unwrap(), rows) {
writeln!(w, "{}", row.strings())?
}
}
else {
self.add_files_to_table(&mut None, &mut rows, &self.files, ignore, TreeDepth::root());
self.add_files_to_table(&mut pool, &mut None, &mut rows, &self.files, ignore, TreeDepth::root());
for row in self.iterate(rows) {
writeln!(w, "{}", row.strings())?
@ -181,13 +184,10 @@ impl<'a> Render<'a> {
/// Adds files to the table, possibly recursively. This is easily
/// parallelisable, and uses a pool of threads.
fn add_files_to_table<'dir, 'ig>(&self, table: &mut Option<Table<'a>>, rows: &mut Vec<Row>, src: &Vec<File<'dir>>, ignore: Option<&'ig IgnoreCache>, depth: TreeDepth) {
use num_cpus;
use scoped_threadpool::Pool;
fn add_files_to_table<'dir, 'ig>(&self, pool: &mut Pool, table: &mut Option<Table<'a>>, rows: &mut Vec<Row>, src: &Vec<File<'dir>>, ignore: Option<&'ig IgnoreCache>, depth: TreeDepth) {
use std::sync::{Arc, Mutex};
use fs::feature::xattr;
let mut pool = Pool::new(num_cpus::get() as u32);
let mut file_eggs = Vec::new();
pool.scoped(|scoped| {
@ -301,7 +301,7 @@ impl<'a> Render<'a> {
rows.push(self.render_error(&error, TreeParams::new(depth.deeper(), false), path));
}
self.add_files_to_table(table, rows, &files, ignore, depth.deeper());
self.add_files_to_table(pool, table, rows, &files, ignore, depth.deeper());
continue;
}
}