- FUNCTIONAL INTERFACE
Digest::xxHash - xxHash Implementation For Perl
use Digest::xxHash qw[xxhash32 xxhash32_hex xxhash64 xxhash64_hex]; my $hash = xxhash32( $data, $seed ); my $hex = xxhash32_hex( $data, $seed ); my $hash_64 = xxhash64( $data, $seed ); my $hex_64 = xxhash64_hex( $data, $seed );
xxHash is an extremely fast algorithm that claims to work at speeds close to RAM limits. This is a wrapper of both the 32- and 64-bit hash functions.
These functions are easy to use but aren't very flexible.
$h = xxhash32( $data, $seed )
Calculates a 32 bit hash.
$h = xxhash32_hex( $data, $seed )
Calculates a 32 bit hash and returns it as a hex string.
$h = xxhash64( $data, $seed )
Calculates a 64 bit hash.
$h = xxhash64_hex( $data, $seed )
Calculates a 64 bit hash and returns it as a hex string.
According to the xxhash project's website, when run in a single thread on a 32bit Windows 7 box with a 3GHz Core 2 Duo processor, xxhash looks a little like:
Name Speed Q.Score Author xxHash 5.4 GB/s 10 CrapWow 3.2 GB/s 2 Andrew MumurHash 3a 2.7 GB/s 10 Austin Appleby SpookyHash 2.0 GB/s 10 Bob Jenkins SBox 1.4 GB/s 9 Bret Mulvey Lookup3 1.2 GB/s 9 Bob Jenkins SuperFastHash 1.2 GB/s 1 Paul Hsieh CityHash64 1.05 GB/s 10 Pike & Alakuijala FNV 0.55 GB/s 5 Fowler, Noll, Vo CRC32 0.43 GB/s 9 MD5-32 0.33 GB/s 10 Ronald L. Rivest SHA1-32 0.28 GB/s 10
Q.Score is a measure of "quality" of the hash function. It depends on successfully passing SMHasher test set. 10 is a perfect score. Hash functions with a Q.score < 5 are not listed in this table.
A 64-bits version, named XXH64, is available since (upstream) r35. It offers much better speed, but for 64-bits applications only.
Name Speed on 64 bits Speed on 32 bits XXH64 13.8 GB/s 1.9 GB/s XXH32 6.8 GB/s 6.0 GB/s
xxHash is covered by the BSD license.
License-wise, I don't actually care about the wrapper I've written.
Sanko Robinson <email@example.com>
xxHash by Yann Collet.