3

BTreeMap/BTreeSet::from_iter: use bulk building to improve the performance by xu...

 2 years ago
source link: https://github.com/rust-lang/rust/pull/88448
Go to the source link to view the article. You can view the picture content, updated content and better typesetting reading experience. If the link is broken, please click the button below to view the snapshot at that time.

Copy link

Contributor

xu-cheng commented 19 days ago

Bulk building is a common technique to increase the performance of building a fresh btree map. Instead of inserting items one-by-one, we sort all the items beforehand then create the BtreeMap in bulk.

Benchmark

./x.py bench library/alloc --test-args btree::map::from_iter
  • Before
test btree::map::from_iter_rand_100                      ... bench:       3,694 ns/iter (+/- 840)
test btree::map::from_iter_rand_10_000                   ... bench:   1,033,446 ns/iter (+/- 192,950)
test btree::map::from_iter_seq_100                       ... bench:       5,689 ns/iter (+/- 1,259)
test btree::map::from_iter_seq_10_000                    ... bench:     861,033 ns/iter (+/- 118,815)
  • After
test btree::map::from_iter_rand_100                      ... bench:       3,033 ns/iter (+/- 707)
test btree::map::from_iter_rand_10_000                   ... bench:     775,958 ns/iter (+/- 105,152)
test btree::map::from_iter_seq_100                       ... bench:       2,969 ns/iter (+/- 336)
test btree::map::from_iter_seq_10_000                    ... bench:     258,292 ns/iter (+/- 29,364)

report

Recommend

About Joyk


Aggregate valuable and interesting links.
Joyk means Joy of geeK