SCHED_ULE should not be the default

O. Hartmann ohartman at mail.zedat.fu-berlin.de
Mon Dec 12 14:09:32 UTC 2011


> Not fully right, boinc defaults to run on idprio 31 so this isn't an
> issue. And yes, there are cases where SCHED_ULE shows much better
> performance then SCHED_4BSD.  [...]

Do we have any proof at hand for such cases where SCHED_ULE performs
much better than SCHED_4BSD? Whenever the subject comes up, it is
mentioned, that SCHED_ULE has better performance on boxes with a ncpu >
2. But in the end I see here contradictionary statements. People
complain about poor performance (especially in scientific environments),
and other give contra not being the case.

Within our department, we developed a highly scalable code for planetary
science purposes on imagery. It utilizes present GPUs via OpenCL if
present. Otherwise it grabs as many cores as it can.
By the end of this year I'll get a new desktop box based on Intels new
Sandy Bridge-E architecture with plenty of memory. If the colleague who
developed the code is willing performing some benchmarks on the same
hardware platform, we'll benchmark bot FreeBSD 9.0/10.0 and the most
recent Suse. For FreeBSD I intent also to look for performance with both
different schedulers available.

O.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 292 bytes
Desc: OpenPGP digital signature
Url : http://lists.freebsd.org/pipermail/freebsd-performance/attachments/20111212/d861bac0/signature.pgp


More information about the freebsd-performance mailing list