Re: opreport on time window of operf data
William Cohen <[email protected]>
| Newsgroups | gmane.linux.oprofile |
|---|---|
| Message-ID | <[email protected]> |
On 03/23/2015 08:24 AM, Henry May wrote: > Is there a way to make opreport only process events that occurred in a subset window of the total operf collection time? I have a long running workload that occasionally sees a spike in L2 misses. I can determine when this happens because throughput drops. I'd like to profile the workload, but only consider events that fall within the window of decreased throughput when generating the opreport. > > Hi Henry, operf doesn't have a convenient mechanism to control when the data is collected. If operf is collecting data for a process that is spawned by operf, it will collect data for the lifetime of the child. As a kludge you might get a smaller duration measurement by having operf attach to the currently running process with "--pid <pid>" option when the dip in throughput starts and then interrupt operf with ctl-c or "kill -2 <operf_pid>" when want to stop data collection. A couple other possible things that might affect L2 performance are other processes polluting/invalidating the cache and the task being migrated between processors. -Will > Henry May > IBM InfoSphere Streams Performance > [email protected] > 720-342-8873 > Tie: 963-8873 > > > ------------------------------------------------------------------------------ > Dive into the World of Parallel Programming The Go Parallel Website, sponsored > by Intel and developed in partnership with Slashdot Media, is your hub for all > things parallel software development, from weekly thought leadership blogs to > news, videos, case studies, tutorials and more. Take a look and join the > conversation now. http://goparallel.sourceforge.net/ > > > > _______________________________________________ > oprofile-list mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/oprofile-list > ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/