[CaCL] [Lab-related] Info on u070

[Jin, Lifeng]

Hi Cocomo members,

There has been some issues with u070. We discovered last week that the 
PBS scheduler somehow thought u070 had only 32 cores, which made some 
jobs which requested 32 cores block all other queued jobs for this 
machine. It has 40 true cores or 80 fake cores with hyper threading.

Now the issue has been addressed, and I would like to make the following 
suggestions:

1. There is an upper limit of 49 cores per machine that can be 
requested, so don't request an excessive amount of cores even if you 
know there should be more cores on a machine, especially if your code is 
not optimized for parallel processing. You can request a ton of memory 
though.

2. u070 is our main (only) GPU powerhouse, so if you plan to use it but 
not the GPUs, try to save a few cores for others who use GPUs. Normal 
GPU jobs don't use a ton of CPU cores. For example, you can request 40 
cores from u070 so that 9 (fake) cores will be left for GPU jobs.

Lifeng