27th of October

Farm status
Intel GPUs
All off

Nvidia GPUs
One running Einstein gravity wave work

Raspberry Pis
All running Einstein BRP4 work

For news on the Raspberry Pis see Marks Rpi Cluster


Other news
Its been warm for the last fortnight so most of the farm has been off. I had all of the Nvidia GPU machines running Einstein gravity wave work on their CPU's last week.


Pimp my storage server
While it was warm I decided to pimp, I mean upgrade, one of the storage servers. Its a 2U rack mount with 12 x 3.5" HDD drive bays. I currently have 4 x 8TB drives which after allowing for single drive redundancy gives a theoretical 24TB usable space, but in practice its 21TB.

I've got lots of spare HDD's but they are of varying sizes from 320GB up to 4TB. These days for a storage server they recommend using the largest size drives available.

The first upgrade was memory. When running ZFS they recommend to increase the memory first as it will use it for caching. Its referred to as the ARC (adaptive replacement cache). I got 8 x 16GB sticks (128GB) which filled all the available RAM sockets. The server supports up to 32GB memory sticks but given its ECC memory it would have cost quite a bit more.

The second upgrade was an Intel Optane 900P 280GB SSD as a cache drive. In ZFS terms its called L2ARC (level 2 adaptive replacement cache). Its a half height PCIe x4 card so you can use it in a 2U server. They're recommended by "Serve the home" as cache drives at the moment.