Server requirements for Opensim - an email from Will to Nick, Monash IT

OpenSim is alpha (or pre-alpha depending on who you ask) software, so reliability and performance is not particularly easy to achieve. Getting it to perform well means getting better hardware than is generally required for other server applications.

The core of OpenSim is a MySQL database, which can get quite large. This means that the server needs to have plenty of RAM and fast disks in order to keep the queries running quickly. Of course, the larger the database becomes as more objects are created, and textures uploaded, the MySQL server will chew through more and more RAM, so it is important to have an excess from the very start.

OpenSim is also a physics simulator, and runs scripts that perform certain actions inside the world. This is done with the CPU, and in quite a highly threaded fashion. Given the option, it may be wiser to choose a CPU (or CPUs) that have more processing threads over the clock speed.

Having said all of this, the RAM and disks are the most important, as the MySQL database is essentially what drives the server. CPU power is also important to have so that the whole thing doesn't die when physics are being simulated.

I am of the understanding that the server might also be used for other purposes, your budget is about $4000-$5000, and your regular server is the R710. So:

CPU:

It appears that the R710 comes with 2 processors (I'm not too sure), so I would say that 2 Quad Core Xeons would suffice. The clock speed should probably be more than 2.2ghz or so.

Operating System:

I forgot to mention this before, but OpenSim is written in C# (.NET) so it can run on both Windows and Linux. .NET is native to Windows of course, so there is added reliability and stability there. We used to run OpenSim on Linux, and it often had problems. I would advise running Windows.

RAM:

As I said before, RAM is important considering that OpenSim relies heavily on a MySQL database. Not only this, but OpenSim caches most things in memory, so memory is used quite a lot. I would recommend a minimum of 8GB, but the more you have, the more room there is for MySQL.

Hard Drives:

The drives need to be fast, but massive amounts of space is not required. I would recommend using 15K drives, and RAID is obviously preferable to keep redundancy and perhaps more speed. Our OpenSim database is about 1.8gb with about 200,000 rows in total, so disk space will be used quite slowly. Even a 146GB 15K drive would probably be fine for quite some time.

Having said all of this, if you can get better parts, definitely go for it, especially in the CPU and Disks. I wouldn't think any more than 12GB of RAM is required, so any extra money should be spent on getting a faster CPU or faster disks.

If you want some more information on OpenSim, there is extensive information on their wiki at http://opensimulator.org/wiki/Main_Page

Will.