Thread:Talk:ResourceLoader/Cache consumption/reply

Ouch, that's a problem. The cache keys in question probably contain the word 'minify' and an md5 hash, right? If so, it's the JS minifier cache, which caches the result of JS minification, and because the same original code always results in the same minified code, it's cached forever as it can never change.

I'm afraid that for now you'll have to periodically purge the objectcache table of keys with this pattern; I've filed a bug about it, and once it's fixed, there will be a patch that you can apply that addresses this behavior. But it may take up to a few months for this patch to get written, unfortunately. An alternative workaround is to use memcached instead of the DB cache; if you have enough users that you're producing >30MB/day in cache cruft, that might be a good idea anyway. memcached uses a fixed maximum size for its cache, and when the cache fills up, it will start throwing out (evicting) old entries, with the least recently used (LRU) entries getting evicted first. This is what we use on our production wikis (Wikipedia and sister sites) as well.

Thanks for the report, this is a quite nasty issue that we hadn't heard about before. We never experienced it ourselves because we use memcached, which is not affected by this problem as it automatically removes unused entries if the cache grows too large.