Online class: Introduction to Biowulf

Hands-On: Freen and batchlim

On the login node or a compute node, run 'freen' and 'batchlim'.

freen

batchlim

Quiz

How many nodes are free in the 'norm' partition?

Answer

Look at the rows corresponding to the norm partition. The second column reports free nodes. e.g.
                                                     .......Per-Node Resources.......
Partition   FreeNds      FreeCPUs          FreeGPUs  Cores  CPUs  GPUs   Mem   Disk  Features
--------------------------------------------------------------------------------------------------------
norm*       0/529        25064/29624       -            28    56     -   246g   400g [...]
norm*       0/1          52/56             -            28    56     -   246g   400g [...]
norm*       0/512        13652/28474       -            28    56     -   248g   800g [...]
norm*       284/486      12418/15552       -            16    32     -   121g   800g [...]
At this moment, there are 284 free nodes in 'norm'.

How many free CPUs are there in the largemem partition?

Answer

The 3rd column in the freen output reports free CPUs. e.g.
largemem    0/4          120/256           -            32    64     -  1005g   800g [...]
largemem    7/20         2012/2880         -            72   144     -  1510g   800g [...]
largemem    3/4          432/576           -            72   144     -  3025g   800g [...]
At this moment there are 120 + 2012 + 432 = 2564 unallocated CPUs in the largemem partition, but only 10 entirely free nodes in that partition. Note that some of these 'unallocated' CPUs may be unallocat-able, because all the memory on those nodes has already been allocated.

Are there any free P100 GPUs?

Answer

Each 'gpu' line in the freen output corresponds to a different kind of GPU. You could determine the free P100 GPUs with a simple grep.
biowulf% freen | grep p100
gpu         38/48        2364/2688         159/192      28    56     4   121g   800g cpu56,core28,g128,ssd650,x2680,ibfdr,gpup100
i.e. at this moment there are 38 completely free P100 GPU nodes.

How many jobs could you have queued and running on Biowulf ?

Answer

'batchlim' reports this at the top.
Max jobs per user: 4000
How many simultaneous interactive sessions can you have?

Answer

'batchlim' reports this:
interactive                64         08:00:00      1-12:00:00 (3 simultaneous jobs)

How many CPUs could you allocate for jobs that last an hour?

Answer

If the cluster was relatively un-busy, you could use the full allocation in norm + the full allocation in the 'quick' partition (+ any allocation in IC-specific partitions to which you have access)