Re: [RT LATENCY] 249 microsecond latency caused by slub'sunfreeze_partials() code.

From: Steven Rostedt
Date: Tue Mar 26 2013 - 12:52:27 EST


On Mon, 2013-03-25 at 14:34 +0000, Christoph Lameter wrote:

> You can eliminate the whole thing by setting
>
> /sys/kernel/slab/<whatever/cpu_partial
>
> to zero.

Giving you an update.

I did the following:

# ls /sys/kernel/slab/*/cpu_partial | while read f; do
echo 0 > $f
done


Then ran our test suite for 24 hours, and had a max latency of 135
microseconds. Well within our range for such a machine. Seems this is
definitely the cause of our latencies, as before, we would always
trigger a unacceptable latency within 12 hours.

Thanks for your help!

-- Steve


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