rust-fastmap

Fast hashmap implementation for Rust.

Might be missing some functionality but you can remove, add, get and clear for now.

Be aware that no effort is made against DoS attacks.

Performace compared to the standard hashmap:

test tests::string_get_built_in    ... bench:  10,146,486 ns/iter (+/- 350,242)
test tests::string_get_fastmap     ... bench:   7,005,050 ns/iter (+/- 126,438)
test tests::string_get_ordermap    ... bench:   7,568,866 ns/iter (+/- 220,864)
test tests::string_insert_built_in ... bench:  11,378,783 ns/iter (+/- 322,641)
test tests::string_insert_fastmap  ... bench:   9,659,826 ns/iter (+/- 183,317)
test tests::string_insert_ordermap ... bench:   7,926,658 ns/iter (+/- 327,210)
test tests::u64_get_built_in       ... bench:      21,275 ns/iter (+/- 379)
test tests::u64_get_fastmap        ... bench:      11,477 ns/iter (+/- 240)
test tests::u64_get_ordermap       ... bench:      22,823 ns/iter (+/- 270)
test tests::u64_insert_built_in    ... bench:      30,093 ns/iter (+/- 381)
test tests::u64_insert_fastmap     ... bench:      18,079 ns/iter (+/- 444)
test tests::u64_insert_ordermap    ... bench:      24,937 ns/iter (+/- 625)

How to use

Simple example.

extern crate fastmap;

use fastmap::FastMap;

let mut map = FastMap::new();

for i in 0..20_000 {
    map.insert(i, format!("item: {:?}", i));
}

Pros and Cons

Pros:

• Faster then the built in hashmap Cons:
• Vunerable to DoS attacks
• Probably use more memory
• Worse worst case performace