Re: Measure time
Der Herr Hofrat <[email protected]>
| Newsgroups | org.kernel.vger.linux-gcc,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
> 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/ hofrat