Re: PREEMPT_RT vs I-PIPE: the numbers, part 2

From: Ingo Molnar
Date: Wed Jun 22 2005 - 16:32:25 EST

* Karim Yaghmour <karim@xxxxxxxxxxx> wrote:

> Hmm... well, I can't say I'm uninterested. Any chances we can get a
> copy of the scripts you use to do the MOAILT (Mother Of All Irq
> Latency Tests).

my 'dohell' script is embarrasingly simple:

while true; do dd if=/dev/zero of=bigfile bs=1024000 count=1024; done &
while true; do killall hackbench; sleep 5; done &
while true; do ./hackbench 20; done &
( cd ltp-full-20040707; su mingo -c ./run40; ) &
ping -l 100000 -q -s 10 -f v &
du / &
./dortc &

and i also start a preloaded flood-ping externally. ./dortc does:

chrt -f 98 -p `pidof 'IRQ 8'`
cd rtc_wakeup
./rtc_wakeup -f 8192 -t 100000

and ./run40 does:

while true; do ./ -x 40; done

it's not rocket science - i'm just starting a sensible mix of latency
generators, without letting any of them dominate the landscape.

> > [ I know the results i am seeing, but i wont
> > post them as a counter-point because i'm obviously biased :-) I'll let
> > people without an axe to grind do the measurements. ]
> That's an extra reason for giving us a copy (or pointing us to one) of
> the script you use to run your tests :)

see above. (It's no secret, i described components of this workload in
one of my first mails to the adeos thread. Btw., what happened to adeos
irq latency testing?)

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