Last modified: 2010-05-15 15:42:52 UTC
I upgraded MediaWiki from 1.7 to 1.8.2 and found that the pages loaded extremely slow; a normal page could suddenly take 20 seconds to load, where it took a fraction of a second with 1.7. In debug.log I happened to see the statement "memcached: Error parsing memcached response", which made me trying to disable memcached. I disabled the lines below in LocalSettings.php and mediawiki behaves normal again. I'm using memcached version 1.1.12. LocalSettings.php: # $wgMainCacheType = CACHE_MEMCACHED; # $wgMemCachedServers = array ( 'localhost:11211' );
Try upgrading to memcached 1.2.0 or 1.1.13. Does this help?
This may or may not be related - I am also having issues with MediaWiki 1.8.2 and memcached 1.1.12. It is stemming from malformed memcached requests - we have a customized sidebar, and it appears that MW is trying to look up the custom captions in memcached. However, the captions contain spaces which result in bad requests: <7 get wiki:messages:Custom sidebar entry >7 END <7 set wiki:messages:Custom sidebar entry 0 86400 17 >7 CLIENT_ERROR bad command line format <7 ###NONEXISTENT### >7 ERROR To memcached, the get request is actually looking for three cache keys: "wiki:messages:Custom", "sidebar", and "entry". None of those exist, so it tries a set command, but because of the spaces memcached doesn't understand the request.
As far as I can remember, most of these problems were solved with an upgrade of memcached and/or some change introduced in 1.8.3, so I'm going to mark this one FIXED; feel free to reopen if it's still broken in a later version.