Hi;
We use node weight parameter to do that. When you set High mem nodes
with high weight, and low mem nodes with low weight; Slurm will select
lowest weight nodes which have enough mem job requested. So, if there
are free low mem nodes, high mem nodes will stay free. At our cluster,
low mem nodes have weight as 10, and high mem nodes have weights 100-400.
Ahmet M.
19.04.2019 18:27 tarihinde Prentice Bisbal yazdı:
Ryan,
I certainly understand your point of view, but yes, this is definitely
what I want. We only have a few large memory nodes, so we want jobs
that request a lot of memory to have higher priority so they get
assigned to those large memory nodes ahead of lower-memory jobs which
could run anywhere else. But we don't want those nodes to sit idle if
there's jobs in the queue that need that much memory. Similar idea for
IB - nodes that need IB should get priority over nodes that don't
Ideally, I wouldn't have such a heterogeneous environment, and then
this wouldn't be needed at all.
I agree this opens another avenue for unscrupulous users to game the
system, but that (in theory) can be policed by looked at memory
requested vs. memory used in the accounting data to identify any
abusers and then give them a stern talking to.
Prentice
On 4/18/19 5:27 PM, Ryan Novosielski wrote:
This is not an official answer really, but I’ve always just
considered this to be the way that the scheduler works. It wants to
get work completed, so it will have a bias toward doing what is
possible vs. not (can’t use 239GB of RAM on a 128GB node). And
really, is a higher priority what you want? I’m not so sure. How soon
will someone figure out that they might get a higher priority based
on requesting some feature they don’t need?
--
____
|| \\UTGERS, |---------------------------*O*---------------------------
||_// the State | Ryan Novosielski - novos...@rutgers.edu
|| \\ University | Sr. Technologist - 973/972.0922 (2x0922) ~*~ RBHS
Campus
|| \\ of NJ | Office of Advanced Research Computing - MSB
C630, Newark
`'
On Apr 18, 2019, at 5:20 PM, Prentice Bisbal <pbis...@pppl.gov> wrote:
Slurm-users,
Is there away to increase a jobs priority based on the resources or
constraints it has requested?
For example, we have a very heterogeneous cluster here: Some nodes
only have 1 Gb Ethernet, some have 10 Gb Ethernet, and others have
DDR IB. In addition, we have some large memory nodes with RAM
amounts ranging from 128 GB up to 512 GB. To allow a user to request
IB, I have implemented that as a feature in the node definition so
users can request that as a constraint.
I would like to make it that if a job request IB, it's priority will
go up, or if it requests a lot of memory (specifically
memory-per-cpu), it's priority will go up proportionately to the
amount of memory requested. Is this possible? If so, how?
I have tried going through the documentation, and googling, but
'priority' is used to discuss job priority so much, I couldn't find
any search results relevant to this.
--
Prentice
