* Fu Juntang(David) ([email protected]) wrote: > Hi,Mathieu: > Please see my answer inline: > > On Thu, 2010-08-12 at 09:40 -0400, Mathieu Desnoyers wrote: > > * Fu Juntang(David) ([email protected]) wrote: > > > Hi,Mathieu: > > > I have found another UST bug in this multi-thread functions: > > > in my SMP host(2 cpu cores),I have found that UST can only collect one > > > thread trace logs running one core(CPU_1),but can not collect the > > > other thread trace logs running another core(CPU_0),is this a known > > > bug? > > > if you need my debug logs, I can attach it to you. > > [...] > > Can you try putting a printf in > > > > ust/libust/buffer.c: get_n_cpus() to see how many CPUs the library > > detects ? > > > yes,sure, the output says that it detects 2 cpus > > > What does your usttrace directory looks like ? (the subdir containing > > the ust and metadata files... with ls -al) > > > total 24 > drwxr-xr-x 2 david david 4096 2010-08-13 15:30 . > drwxr-xr-x 3 david david 4096 2010-08-13 15:30 .. > -rw------- 1 david david 4096 2010-08-13 15:30 metadata_0 > -rw------- 1 david david 4096 2010-08-13 15:30 metadata_1 > -rw------- 1 david david 4096 2010-08-13 15:30 ust_0 > -rw------- 1 david david 4096 2010-08-13 15:30 ust_1 >
It all looks fine so far. Note that the Linux scheduler can decide to schedule your 2 threads on the same CPU. How do you detect that there is a "problem": is it that events you are writing from a specific thread are missing or that you expect events on CPU 1 and don't have any ? The latter case could be normal. Thanks, Mathieu -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com _______________________________________________ ltt-dev mailing list [email protected] http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
