[Koha] Koha resource requirements

[Barry Callahan]

I recently started playing with Koha to see if it would help my wife and I manage our home library.

 
Before I began, I reviewed the requirements listed on the download page ( https://koha-community.org/download-koha/ ) and the instructions for installing using the official .deb packages. One thing I thought was very conspicuously lacking was any mention of resource requirements. Naively, I assumed that meant that the requirements for running Koha would only be minimally greater than those required for a LAMPP stack serving a similar amount of traffic.

 
Needless to say, an Amazon EC2 micro instance, which only has 1GB of RAM allocated to it is incapable of creating and enabling a single Koha library instance. Attempting to do so with no swap enabled immediately resulted in a crashed system.

 
I resized the instance to small, with 2GB of RAM, and was able to boot the system and log in, but top showed a peak memory usage of ~1.9GB. On seeing that, I resized the server again to a medium instance with 4GB of RAM. After populating the database and adding a couple users and a few dozen items to it, the server is sitting at 1.5GB of RAM in use (not including cache) at idle. Admittedly, that includes the 500MB allocated to the local MySQL server, but still. I think I could probably be safe scaling back to a small instance if I moved the database to a remote server, which is my plan.

 
I'd like to suggest updating the requirements section on the download page to include some information on the resources used by the koha-plack stack. At a minimum, some information about how much koha+plack would add to the memory footprint of an existing LAMP stack at idle would have saved me a fair bit of grief. Some information on how RAM usage and CPU load can be expected to scale with the number of active library instances and concurrent users would be nice, too, but less important than the base numbers, I think.