Hi, On Wed, Oct 20, 2010 at 12:09 PM, xudi <x...@ict.ac.cn> wrote: > hi all, > > I am new to libpfm v4. I read the example code "task_smpl.c", which uses > random sampling periods, but I didn't find any explicit statement to turn > this feature on. >
There is no sampling randomization support in perf_events. What you have is two modes: 1- fixed period 2- target average sample rate In the first mode, you set the period and it is used for each sample. In the second mode, you set a target frequency, e.g., 1000Hz, which means you'd like to get about 1000 samples/sec. The kernel will adjust the sampling period dynamically to achieve the target average frequency. The frequency is adjusted every timer tick. In task_smpl, you can select either mode: fixed period: task_smpl -p 2400000000 ....... frequency: task_smpl -p 1000 -f ...... > So, how to turn off sampling period randomization? > > I am using the official Linux 2.6.35 kernel. > > Thanks. > > 2010-10-20 > ________________________________ > Di Xu > ICT, CAS > ------------------------------------------------------------------------------ > Download new Adobe(R) Flash(R) Builder(TM) 4 > The new Adobe(R) Flex(R) 4 and Flash(R) Builder(TM) 4 (formerly > Flex(R) Builder(TM)) enable the development of rich applications that run > across multiple browsers and platforms. Download your free trials today! > http://p.sf.net/sfu/adobe-dev2dev > _______________________________________________ > perfmon2-devel mailing list > perfmon2-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/perfmon2-devel > > ------------------------------------------------------------------------------ Nokia and AT&T present the 2010 Calling All Innovators-North America contest Create new apps & games for the Nokia N8 for consumers in U.S. and Canada $10 million total in prizes - $4M cash, 500 devices, nearly $6M in marketing Develop with Nokia Qt SDK, Web Runtime, or Java and Publish to Ovi Store http://p.sf.net/sfu/nokia-dev2dev _______________________________________________ perfmon2-devel mailing list perfmon2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/perfmon2-devel
