Running out of hardware resources?

[Chris Clawson]

              

What are the reliable minimum server requirements for a DSpace 7 installation?

Our installation is funded out-of-pocket and we just can't afford the kind of professional hosting expected for major institutions.

Am I running out of system resources? Here is my overview:

Non-managed KVM virtual server

Ubuntu 20.04

4 CPU cores

4GB RAM

1GB swap

The system load is very light, but RAM usage is now typically 97% capacity and swap varies around 80%. We have items with 30 or more images. The Mirador viewer does work reliably, but the thumbnail generation is taking more time than we'd like to see.

Tomcat 9

Apache 2

PostgreSQL

MySQL

Cantaloupe image server

DSpace 7.2

Wordpress

Would another GB of RAM speed performance up and prevent bitstream upload errors? It will cost more to find out.

[Tim Donohue]

Hi Chris,

You haven't let us know what sort of errors you are seeing... but, it does (at a glance) sound like you are running a *lot* under very little resources.  It sounds like you are running DSpace + Wordpress  (and all their pre-requisites) with just 4GB of memory total?  That's impressive, as I'd expect either DSpace alone would want at least 4GB of memory (and Wordpress may require something similar).

Overall, if you want to run everything DSpace requires on one server, I think you'd need 4GB at a minimum *just for DSpace*.  Inspired by your question, I went ahead and wrote up some "bare minimum requirements" based on what works for me on a memory-controlled Docker setup of DSpace 7.

https://wiki.lyrasis.org/display/DSDOC7x/Performance+Tuning+DSpace#PerformanceTuningDSpace-BareMinimumRequirements

I believe these requirements to be accurate, but it's possible we'll need to tweak them based on what others report in production scenarios.  In any case, I do think you will need to think about either adding RAM, or alternatively finding a separate server for either the frontend or backend (as you do not need to run both on the same server).  You also may need to look closely at Wordpress & MysSQL memory requirements, as they could also have an impact on your memory usage & therefore DSpace's performance.

Tim

[Chris Clawson]

Well, no hard and repeatable errors. Dragging a group of images (at one time) into an item may unpredictably fail individual images, while correctly uploading others. If an item contains 30 images, the iiif server takes time to generate the thumbnails in the navigator bar. To repeat, I might get into big trouble if our server ever experienced any real demand. Since this posting, we have added an additional 1GB of ram. The installation quickly found it and we are back to about 140Mb of free memory, although I notice the cache memory settles around 900Mb. Over all, I suppose we are doing well for a $20/mo. virtual machine.