On Mon, May 18, 2009 at 11:22 AM, Bart Van Assche <[email protected]> wrote: > On Mon, May 18, 2009 at 6:52 PM, Sufficool, Stanley > <[email protected]> wrote: >> IIRC, The SRP Target code has many context switches that throttle >> performance at higher thread counts. > > Depends on which version of ib_srpt you are using. The ib_srpt kernel > module has a parameter called "thread" which allows to control whether > disk I/O is handled in another thread than the one that communicates > over InfiniBand (thread=1) or in the same thread (thread=0). For older > versions of the ib_srpt kernel module the default was thread=1, which > caused indeed a lot of context switches. On December 3, 2008 (SCST > Subversion revision 594) the default has been changed from thread=1 to > thread=0 because the latter results in better performance.
I won't have access to the targets until tomorrow (at which point I may not have internet access), so I'm trying to gather a few possible solutions today. I'm using a very recent version of the SCST target code, it would only be ~1 month old. So, I'm guessing I have the "thread=0" code. Maybe, for a high thread count, this needs to be "=1"? Is there a way to control the number of threads once "thread=1" is set? Does it spawn one thread per initiator thread? Any other ideas of things to try? Thanks, Chris > > Bart. > _______________________________________________ general mailing list [email protected] http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
