I am a sql-clueless person. So can someone explain me why the --- we have myisam there, if it performs so bad? Ber Op donderdag 29 december 2005 18:24, schreef John Handelaar:
In the continuing absence of anywhere to discuss these performance edge-cases (more below)...
I've already mentioned recently that MyISAM is the enemy of Drupal performance. Because it requires a full-table lock, if you have lots of active members logged in at once, the process of posting a comment causes page rendering to cease entirely for several seconds.
Onto today's point:
The same table-level locking is *lethal* on a heavily- trafficked site which has both
a) Content which alters regularly (like a busy forum), and
b) Caching turned on.
Try turning it off if your slow query log starts showing cache-related things taking 90 seconds (!) or more (!!).
And then take a backup of your database and change these table types to InnoDB format.
And then start looking at delayed inserts.
jh
PS: Still no bigsite/performance forum. Have we decided that Drupal doesn't *need* to scale? I missed that meeting.