Hi Phillip, Thanks for the response.
I guess I don't know much about hardware to at least have some direction. >From what I have read, it seems like timers implemented with the hpet device could give me the granularity I am looking for. If I understand correctly, the getitimer function in Linux uses hpet. The problem of using busy loop is that the CPU should be free for the benchmark I want to run. In case it is relevant, the machine is an AMD Opteron with nVidia motherboard. Luis. On Sat, Oct 9, 2010 at 2:40 AM, Philip Guenther <[email protected]> wrote: > On 9/29/10, Luis Useche <[email protected]> wrote: > > I need to read a performance monitoring counter (RDPMC) every 100 > > microseconds or so. I found a way to do this on linux using the normal > > getitimer library. However, the resolution of this timer in OBSD is 10 > > milliseconds. Do you know a way to have a higher resolution of the timer > in > > OBSD? One way is to do a busy loop, but this is not feasible in my > problem. > > You don't really give enough information to give good advice > (platform? how is the RDPMC read? notice how many replies you've > gotten?), but depending on the details, writing a kernel driver may be > the most natural way. Otherwise, a busy loop in userspace watching > the CPU's performance counter might be an option. > > > Philip Guenther
