If this is on a IA32(Pentium II or later)/IA64 have you considered using
the processor TSC register to get interval timestamps? It's a lot
lighter weight and should give better resolution. When we have done this
we compared the tick values directly.
To convert TSC ticks to time the /proc/cpuinfo value for 'cpu MHz', see
the glibc get_clockfreq.c and hp_timing.h implementation for details.
Dave Howell
-----Original Message-----
From: Maciej Soltysiak [mailto:solt@dns.toxicfilms.tv]
Sent: Tuesday, January 14, 2003 2:58 PM
To: linux-kernel@vger.kernel.org
Subject: timing an application
Hi,
being inspired by some book about optimizing c++ code i decided to do
timing of functions i wrote. I am using gettimeofday to set
two timeval structs and calculate the time between them.
But the results depend heavily on the load, also i reckon that this
is an innacurate timing.
Any ideas on timing a function, or a block of code? Maybe some kernel
timers or something.
Regards,
Maciej Soltysiak
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