Messages in this thread | | | Date | Tue, 10 Apr 2001 14:45:15 -0400 | From | "Stephen D. Williams" <> | Subject | Re: No 100 HZ timer ! |
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When this is rewritten, I would strongly suggest that we find a way to make 'gettimeofday' nearly free. Certain applications need to use this frequently while still being portable. One solution when you do have clock ticks is a read-only mapped Int. Another cheap solution is library assembly that adds a cycle clock delta since last system call to a 'gettimeofday' value set on every system call return.
sdw
Andi Kleen wrote: > > On Tue, Apr 10, 2001 at 01:12:14PM +0100, Alan Cox wrote: > > Measure the number of clocks executing a timer interrupt. rdtsc is fast. Now > > consider the fact that out of this you get KHz or better scheduling > > resolution required for games and midi. I'd say it looks good. I agree > > And measure the number of cycles a gigahertz CPU can do between a 1ms timer. > And then check how often the typical application executes something like > gettimeofday. > ...
sdw -- sdw@lig.net http://sdw.st Stephen D. Williams 43392 Wayside Cir,Ashburn,VA 20147-4622 703-724-0118W 703-995-0407Fax Dec2000 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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