SCHED_ULE?

[M. Warner Losh]

In message: <43EE151E-574E-4A17-9946-0BC5A6B3BC69 at freebsd.org>
            Rui Paulo <rpaulo at freebsd.org> writes:
: Hi,
: 
: On 10 Nov 2009, at 04:38, Sam Leffler wrote:
: 
: > Olivier Houchard wrote:
: >> On Sun, Nov 08, 2009 at 01:30:48PM +0000, Rui Paulo wrote:
: >>> Hi,
: >>> I guess this has been discussed in the past but, can't we turn on ULE  on ARM embedded systems ? What's the bottleneck or performance  regression (assuming there's one) ?
: >>> 
: >>> --
: >>> Rui Paulo
: >> Hi,
: >> At one point ULE was buggy on arm, but I think it's been fixed like years ago,
: >> so it should be safe to use it.
: > 
: > Last I measured it was slower than 4BSD on my xscale boards (not much but measurable).  This was mostly doing network packet pushing (wired+wireless).
: 
: I also tested this on the Cambria board and I concluded the same (I used sysbench).

This isn't too surprising, since it is optimized for multicore and
4BSD grew up on single-core systems...

Warner