crypto:md5 vs erlang:md5 ------------------------ Key: COUCHDB-757 URL: https://issues.apache.org/jira/browse/COUCHDB-757 Project: CouchDB Issue Type: Improvement Environment: GNU/Linux Reporter: Filipe Manana Attachments: crypto_md5.patch
Just noticed that crypto:md5 is faster than erlang:md5 by about an order of magnitude when hashing just 8Kb or 4Kb of data. Basically we use md5 hashing when writing and reading documents and attachments through couch_file and couch_stream. Eshell V5.8 (abort with ^G) 1> crypto:start(). ok 2> Bin1 = crypto:rand_bytes(4 * 1024). <<92,239,233,29,1,237,96,193,188,97,4,72,51,90,96,91,187, 112,112,198,7,173,105,99,205,65,105,94,144,...>> 3> 3> {T1, _} = timer:tc(erlang, md5, [Bin1]). {211, <<20,235,111,74,212,254,194,144,49,70,205,105,124,106, 131,230>>} 4> 4> {T2, _} = timer:tc(crypto, md5, [Bin1]). {60, <<20,235,111,74,212,254,194,144,49,70,205,105,124,106, 131,230>>} 5> 5> Bin2 = crypto:rand_bytes(8 * 1024). <<246,66,158,227,62,127,62,239,202,232,133,244,191,9,136, 6,164,179,109,166,253,41,144,185,177,39,177,88,142,...>> 6> 6> {T3, _} = timer:tc(erlang, md5, [Bin2]). {446, <<7,55,252,42,249,30,58,22,245,12,111,82,131,58,199,51>>} 7> 7> {T4, _} = timer:tc(crypto, md5, [Bin2]). {77, <<7,55,252,42,249,30,58,22,245,12,111,82,131,58,199,51>>} 8> I know there's a ticket around with the goal of the possibility to remove the dependency on the crypto module, but for environments where this is not a problem it would be a plus. Made a test that wrote 400 attachments with about 60Kbs and noticed an average response time of 0.16s versus 0.18s (erlang:md5). -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.