Topic on Project:Support desk/Flow

I've just created a new (empty) Mediawiki installation on php7.0 in docker. I'm using Ubuntu 16.04 and a MySQL instance from Amazon's RDS. The wiki is very slow. It takes around 5 seconds to load any page. It takes around 8 seconds to write to a page.

What am I doing wrong? I have the default LocalSettings.php that was generated by the installation process. I've tried setting apache trace8, monitoring DNS via tcpdump, also using mediawiki debug. I cannot see what's taking the time, all processes just seem slow.

You may need to enable caching. in-memory object caching improves performance a lot. See Manual:$wgMainCacheType. Use memcached or redis.

One thing I noticed: If I go through the exact same installation process *outside* of docker (a regular EC2 instance), the wiki is fast. If I install *inside* docker the result is an extremely slow wiki. I've tried a few different versions of Ubuntu, Mediawiki and PHP.

Note that docker is running another OS inside it, which adds yet another layer of CPU and disk usage. My guess is that EC2 instances, being already a virtualized machine inside another machine, may not be optimized to handle yet another virtualized machine inside it.

Also, PHP and MediaWiki may require a fair amount of available RAM, that if not present, could lead to swap to disk, increasing the slowness.

Docker is container virtualization. There isn't "another OS inside it". It's not virtualized hardware.

You're right about that, I didn't know those details when I replied 4 years ago. Problem may be caching, available CPU cores, disk speed...