Call for testers, significant sched_lock patch.

Abdullah Ibn Hamad Al-Marri almarrie at
Mon Jun 4 00:29:49 UTC 2007

On 6/1/07, Jeff Roberson <jroberson at> wrote:
> I am going to commit a patch that goes significantly towards decomposing
> the scheduler lock into per-cpu scheduler locks.  Before this, I would
> like it if a few more people would run it under more circumstances than I
> have.  The patch is available at:
> So far Kris Kennaway and myself have tested it fairly thoroughly on amd64
> machines with 1-8 processors.  We've mainly done various benchmarks as
> well as Peter Holm's stress2 suite.  It has survived our testing so this
> isn't totally unstable code.  I would like it if more people would test
> on any other architecture you have available.  I have also tested with
> 4BSD and ULE with and without INVARIANTS and WITNESS.
> This patch should have 0 or almost 0 effect on performance.  It sets the
> stage for a drop-in replacement for ULE that has per-cpu run queue locks.
> That scheduler has a sometimes dramatic effect on performance, depending
> on the workload.  I'm mostly looking for regressions here and not any
> particular perf impact.
> Any questions on the design of the approach should be directed at the
> arch@ topics on the subject.
> Thanks,
> Jeff

I wish we could try it in i386, do you have plans to do it?


-Abdullah Ibn Hamad Al-Marri
Arab Portal

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