On 03/15/16 at 03:12pm, "Zhou, Wenjian/???" wrote: > Hello Minfei, > > I guess the result is affected by the caches. > How about executing the following command before running makedumpfile each time? > # echo 3 > /proc/sys/vm/drop_caches All of cache will be dropped before starting new test. Hmm, it is limited to debug in kdump kernel. I will use "strace" to debug it later. Thanks Minfei > > -- > Thanks > Zhou > > On 03/15/2016 02:34 PM, Minfei Huang wrote: > >Hi, Zhou. > > > >I have applied this patch base on 1.5.9. There are several testcases I > >have tested. > > > >- makedumpfile --num-threads 64 -d 31 > > real 0m0.010s > > user 0m0.002s > > sys 0m0.009s > > > >- makedumpfile --num-threads 31 -d 31 > > real 2m40.915s > > user 10m50.900s > > sys 23m9.664s > > > >makedumpfile --num-threads 30 -d 31 > > real 0m0.006s > > user 0m0.002s > > sys 0m0.004s > > > >makedumpfile --num-threads 32 -d 31 > > real 0m0.007s > > user 0m0.002s > > sys 0m0.005s > > > >- makedumpfile --num-threads 8 -d 31 > > real 2m32.692s > > user 7m4.630s > > sys 2m0.369s > > > >- makedumpfile --num-threads 1 -d 31 > > real 4m42.423s > > user 7m27.153s > > sys 0m22.490s > > > >- makedumpfile.orig -d 31 > > real 4m1.297s > > user 3m39.696s > > sys 0m15.200s > > > >This patch has a huge increment to the filter performance under 31. But > >it is not stable, since makedumpfile fails to dump vmcore intermittently. > >You can find the above test result, makedumpfile fails to dump vmcore > >with option --num-threads 64, also it may occur with option > >--number-threads 8. > > > >Thanks > >Minfei
