Messages in this thread | | | Date | Thu, 24 Jun 2004 12:13:11 +0530 | From | abhijit <> | Subject | Re: do_gettimeofday( ) precision? |
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On Wed, 23 Jun 2004 17:54:13 +0200 (CEST), Lukasz Michal Rak <l.rak@elka.pw.edu.pl> wrote:
> I don't know the way how to do it, but I wonder about > precision of such mechanism (if any exists).
basically i want some counter w/ microsend resolution that fits into 32 bits. couple of possible solutions come to my mind:
[1] use TSC and convert it to microsec [2] use get_timeofday( ) and convert to microsec [3] use xtime variable directly and convert to microsec (any other ways?)
conversion in [1] will be costly (a div involved). conversion in [2]/[3] can be done using bit operators. (usec|sec << 20) but [2] will incur function call overhead which i'd like to avoid.
so is using xtime directly ok and reliable?
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