On Fri, 2009-10-02 at 20:57 +0200, Mike Galbraith wrote: > On Fri, 2009-10-02 at 20:19 +0200, Jens Axboe wrote: > > > I'm not too worried about the "single IO producer" scenarios, and it > > looks like (from a quick look) that most of your numbers are within some > > expected noise levels. It's the more complex mixes that are likely to > > cause a bit of a stink, but lets worry about that later. One quick thing > > would be to read eg 2 or more files sequentially from disk and see how > > that performs. > > Hm. git(s) should be good for a nice repeatable load. Suggestions? > > > If you could do a cleaned up version of your overload patch based on > > this: > > > > http://git.kernel.dk/?p=linux-2.6-block.git;a=commit;h=1d2235152dc745c6d94bedb550fea84cffdbf768 > > > > then lets take it from there. > > I'll try to find a good repeatable git beater first. At this point, I > only know it helps with one load. Seems to help mixed concurrent read/write a bit too. perf stat testo.sh Avg 108.12 106.33 106.34 97.00 106.52 104.8 1.000 fairness=0 overload_delay=0 93.98 102.44 94.47 97.70 98.90 97.4 .929 fairness=0 overload_delay=1 90.87 95.40 95.79 93.09 94.25 93.8 .895 fairness=1 overload_delay=0 89.93 90.57 89.13 93.43 93.72 91.3 .871 fairness=1 overload_delay=1 #!/bin/sh LOGFILE=testo.log rm -f $LOGFILE echo 3 > /proc/sys/vm/drop_caches sh -c "(cd linux-2.6.23; perf stat -- git checkout -f; git archive --format=tar HEAD > ../linux-2.6.23.tar)" 2>&1|tee -a $LOGFILE & sh -c "(cd linux-2.6.24; perf stat -- git archive --format=tar HEAD > ../linux-2.6.24.tar; git checkout -f)" 2>&1|tee -a $LOGFILE & sh -c "(cd linux-2.6.25; perf stat -- git checkout -f; git archive --format=tar HEAD > ../linux-2.6.25.tar)" 2>&1|tee -a $LOGFILE & sh -c "(cd linux-2.6.26; perf stat -- git archive --format=tar HEAD > ../linux-2.6.26.tar; git checkout -f)" 2>&1|tee -a $LOGFILE & wait -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel