2006-06-28
memcached performance
two interesting posts arrived on the memcached list which might be interesting to performance people.
The first was a comparison of "The fastest lanugage binding":http://dealnews.com/developers/memcached.html on which 'P' language performed better. To make a note the PHP version actually uses "libmemcache":http://people.freebsd.org/~seanc/libmemcache/ a 'C' library which goes a bit of the way to explain the wild disparity in speeds.
The 2nd more interesting one (to me) was the "discussion":http://lists.danga.com/pipermail/memcached/2006-June/002384.html of how "Digg":http://digg.com switched from using mysql to memcached with v3 of their new interface to handle storing sessions, due to a hardware crash on their mysql server.
others mentioned using InnoDB for this instead of MyISAM, with the biggest issue being clearing out expired sessions (which memcached does for you with less overhead), but storing the sessions in the database still suffered due to OS-contention.
of course with django you can choose "either":http://www.djangoproject.com/documentation/cache/, to cache your stuff.. but the session handling is stored directly in the database .. looks like I have a weekend project ;-)