[Vagnekman-users] Reminder: Configuration change of the login node

[Michael Schliephake]

Dear Users,

as I informed a few days before, we have set a configuration which enforces a limit on the resource usage on the login node of Ekman. This is necessary to avoid disturbations of other users by resource overuse.

Aside the mentioned compilations also long-lasting file transfers can be affected. Because you have the possibility to login from the outside to every cluster node it is also possible to execute file transfers on dedicated jobs interactively or even in batch jobs which give the node free if the work is done.

I am sorry if you face some inconveniences due to the configuration change which implies maybe changes in your procedures. But please consider also that the login node is shared resource. It is in the interest of all users that demanding things which not mandatory have to be done there will be executed at the cost of the availability for other users.


Best regards -- Med vänlig hälsning

Michael
-- 
KTH Royal Institute of Technology
PDC Center for High Performance Computing
Teknikringen 14, SE-100 44 Stockholm, Sweden
Phone: +46-8-790 78 22, Mobile: +46-73-460 78 22

Vidarebefordrat brev:

> Från: Michael Schliephake <michs at kth.se>
> Datum: 15 november 2010 23.34.49 CET
> Till: "vagnekman-users at snic.vr.se" <vagnekman-users at snic.vr.se>
> Ämne: Configuration change of the login node
> 
> Dear Users,
> 
> today we had a problem with memory overuse on the login node. Therefore we established here limits which showed helpful already on other systems like Ferlin. 
> 
> All user processes are limited now to
> 
>  * 10 minutes of CPU time
>  * 8 GByte RAM, th.i. 50% of the machine RAM.
> 
> So it should be not so easy to bring the login node in an unstable state.
> 
> The consequence is that some resource hungry things you may have done before on the login node will not work longer. For example can this be a compilation of a large source file with the Inel compiler and  IPO (inter procedure optimization) turned on.
> 
> Please use for these works a node which you acquire with the help of easy. The use of dedicated nodes will disturb other users much less.
> 
> If it is desired we could also establish one or two interactive nodes where you can login without a job submission. 
> 
> 
> Best regards -- Med vänlig hälsning
> 
> Michael Schliephake
> -- 
> KTH Royal Institute of Technology
> PDC Center for High Performance Computing
> Teknikringen 14, SE-100 44 Stockholm, Sweden
> Phone: +46-8-790 78 22, Mobile: +46-73-460 78 22
>