Is this client CPU or server CPU? If you are using Ethernet it will definitely be CPU hungry and can easily saturate a single core.
Cheers, Andreas On 2010-10-20, at 8:41, Michael Kluge <[email protected]> wrote: > Hi list, > > is it normal, that a 'dd' or an 'IOR' pushing 10MB blocks to a lustre > file system shows up with a 100% CPU load within 'top'? The reason why I > am asking this is that I can write from one client to one OST with 500 > MB/s. The CPU load will be at 100% in this case. If I stripe over two > OSTs (which use different OSS servers and different RAID controllers) I > will get 500 as well (seeing 2x250 MB/s on the OSTs). The CPU load will > be at 100% again. > > A 'dd' on my desktop pushing 10M blocks to the local disk shows 7-10% > CPU load. > > Are there ways to tune this behavior? Changing max_rpcs_in_flight and > max_dirty_mb did not help. > > > Regards, Michael > > -- > > Michael Kluge, M.Sc. > > Technische Universität Dresden > Center for Information Services and > High Performance Computing (ZIH) > D-01062 Dresden > Germany > > Contact: > Willersbau, Room A 208 > Phone: (+49) 351 463-34217 > Fax: (+49) 351 463-37773 > e-mail: [email protected] > WWW: http://www.tu-dresden.de/zih > _______________________________________________ > Lustre-discuss mailing list > [email protected] > http://lists.lustre.org/mailman/listinfo/lustre-discuss _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
