On 03/10/2011 10:16 AM, Craig Tierney wrote: > On 3/10/11 9:49 AM, Paul Van Allsburg wrote: >> Hi All, >> I want to make a ramdisk available to cluster users and I'm curious what >> your experiences/suggestions might be. I'm adding 40 >> machines to a cluster that have 24 gig of ram. I'd like to offer the option >> of allowing some users to be able to run a job on a >> machine with 20 gig carved out for a ram disk. >> >> The cluster is running centos 5.5 with torque& maui. >> >> I expect the user will have to request one machine for the job and have the >> prologue/eplogue scripts mount& unmount the >> ramdisk. Are there any success / horror stories that I might be enlightened >> by? >> >> Thanks! >> Paul >> > > As far as I recall, Centos creates a ramdisk by default at /dev/shm whose > maximum size is 1/2 of available memory. The ramdisk uses available memory > as needed, and doesn't block an application from allocating > all of memory (as long as there is nothing in the ramdisk).
No, don't use /dev/shm - this is a API mount for posix shared memory. Mount another tmpfs somehwere else (we mount one at /tmp). tmpfs is very nice, just remember that is competes with the RAM demands of your processes. -- Orion Poplawski Technical Manager 303-415-9701 x222 NWRA/CoRA Division FAX: 303-415-9702 3380 Mitchell Lane [email protected] Boulder, CO 80301 http://www.cora.nwra.com _______________________________________________ Beowulf mailing list, [email protected] sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
