Re: Measure time
"Calin A. Culianu" <[email protected]>
| Newsgroups | org.kernel.vger.linux-gcc,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
On Wed, 8 May 2002, Der Herr Hofrat wrote: > > Hello! > > > > Is there any function for high precision time measuring. > > time() returns only in second. I need nanoseconds. > > > you can directly read the TSC but that will not realy give you nanoseconds > resolution as the actual read access even on a PIII/1GHz is going to take > up to a few 100 nanoseconds, and depending on what you want to time > stamp the overall jitter of that code can easaly be in the > range of a microsecond. > > There are some hard-realtime patches to the Linux kernel that will > allow time precission of aprox. 1us (the TSC has a precission of 32ns) > but I don't think you can get below that without dedicated hardware. > > for RTLinux check at ftp://ftp.rtlinux.org/pub/rtlinux/ I recommend RTAI instead. It's more feature-rich, and works with newer kernels.. the url is http://www.aero.polimi.it/~rtai/, or http://www.rtai.org. -Calin > > hofrat > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >