Messages in this thread | | | Subject | Re: big picture UDP/IP performance question re 2.6.18 -> 2.6.32 | From | Joe Perches <> | Date | Tue, 04 Oct 2011 12:38:38 -0700 |
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On Tue, 2011-10-04 at 14:16 -0500, Christoph Lameter wrote: > On Mon, 3 Oct 2011, starlight@binnacle.cx wrote: > > I've come to the conclusion that Eric is right > > and the primary issue is an increase in the > > cost of scheduler context switches. Have > > been watching this number and it has held > > pretty close to 200k/sec under all scenarios > > and kernel versions, so it has to be > > a longer code-path, bigger cache pressure > > or both in the scheduler. Sadly this makes > > newer kernels a no-go for us. > We had similar experiences. Basically latency constantly gets screwed up > by the new fancy features being added to the scheduler and network > subsystem (most notorious is the new "fair" scheduler, 2.6.23 made a big > step down).
Idly curious, have you compared bfs performance? http://ck.kolivas.org/patches/bfs/bfs-faq.txt
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