[patch] voluntary-preempt-2.6.8.1-P5

Ingo Molnar
2004-08-20T13:29:15Z

i've uploaded the -P5 patch:

http://redhat.com/~mingo/voluntary-preempt/voluntary-preempt-2.6.8.1-P5

Changes since -P4:

- increase PERCPU_ENOUGH_ROOM to avoid percpu overflow on SMP.
(Mark H Johnson)

- reduce ZAP_BLOCK_SIZE to 16 when vp != 0. This pushes the exit
latency down to below 100 usecs on Lee Revell's box.

- added a preempt_count field to /proc/latency_trace. This makes it
easier to spot IRQ contexts and generally it gives a nice overview of
how the preemption depth changes. It should also help us debug
those 900usec weirdnesses related to cpu_idle. (if they still occur)

- made the tcp packet-queue collapsing dependent on VOLUNTARY_PREEMPT.

- fixed 10-20 msec latencies triggered by 'netstat', which occur when
there are lots of sockets on a box.

- rediffed against 2.6.8.1 for the patch to apply without fuzz

Ingo