On Tue, Aug 16, 2016 at 02:30:04PM +0000, Bodireddy, Bhanuprakash wrote: > >-----Original Message----- > >From: Daniele Di Proietto [mailto:diproiet...@ovn.org] > >Sent: Tuesday, August 16, 2016 1:44 AM > >To: Bodireddy, Bhanuprakash <bhanuprakash.bodire...@intel.com> > >Cc: dev@openvswitch.org; Flavio Leitner <f...@sysclose.org> > >Subject: Re: [PATCH V6] netdev-dpdk: Set pmd thread priority > > > >I found a crash if apply this patch, "dpdk-lcore-mask" is not set and "-c > >0x1" is > >passed to "dpdk-extra". > My bad, I didn't test with dpdk-extra options. I see that the crash was due > to strtol. > > >Also, I believe Flavio had a comment on the previous version of this > >patch. Would it be enough to use setpriority(2)? > I sent out my comments in another mail. I agree to Flavio's suggestion as > this seems less dangerous and > is guaranteed to work even in case of misconfiguration. I tested this > approach and have a concern with > setpriority(). > > To apply the new nice value to the thread, thread id is needed and due to > absence of glibc wrapper > for gettid, I have to use syscall(SYS_gettid). I want to know if this is > acceptable in OVS or better way to handle this? > > Void ovs_numa_thread_setpriority(int nice OVS_UNUSED) > { > .... > #if defined(__linux__) && defined(SYS_gettid) > pid_t tid = syscall(SYS_gettid); > err = setpriority(PRIO_PROCESS, tid, nice); > .... > #endif > }
I don't know a better way to implement this and it seems ovs-numa.c already has some ifdefs specific to linux. Do you know if this problem happen on BSD? > Without priority patch: > > $ ps -eLo tid,pri,psr,comm | grep -e lcore -e revalidator -e ovs-vswitchd -e > pmd > 22509 19 4 ovs-vswitchd > 22512 19 5 lcore-slave-5 > 22513 19 6 lcore-slave-6 > 22514 19 7 lcore-slave-7 > 22589 19 4 revalidator37 > 22590 19 4 revalidator52 > 22591 19 4 revalidator42 > 22592 19 4 revalidator38 > 22593 19 4 revalidator39 > 22594 19 4 revalidator45 > 22595 19 4 revalidator53 > 22596 19 4 revalidator54 > 22598 19 4 pmd61 [Default priority] > > With priority patch: > > $ ps -eLo tid,pri,psr,comm | grep -e lcore -e revalidator -e ovs-vswitchd -e > pmd > 24879 19 4 ovs-vswitchd > 24881 19 5 lcore-slave-5 > 24882 19 6 lcore-slave-6 > 24883 19 7 lcore-slave-7 > 24951 19 4 revalidator55 > 24952 19 4 revalidator37 > 24953 19 4 revalidator52 > 24954 19 4 revalidator42 > 24955 19 4 revalidator38 > 24956 19 4 revalidator39 > 24957 19 4 revalidator45 > 24958 19 4 revalidator53 > 24964 39 4 pmd61 [Higher priority set] Looks good, so if you affinity your bash to the CPU running pmd61 thread, are you able to use it? Thanks, -- fbl _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
