Messages in this thread |  | | Date | Fri, 17 Nov 2000 08:08:17 -0500 | From | Jeff Garzik <> | Subject | Re: Error in x86 CPU capabilities starting with test5/6 |
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Christoph Rohland wrote: > > Hi Alan, > > On Fri, 17 Nov 2000, Alan Cox wrote: > > Even checking the cpuinfo for the TSC should be done with care, and > > its far far better to use gettimeofday unless doing very tiny > > timings (eg for optimising code paths) > > gettimeofday is _way_ to slow for a lot of every day uses. So > applications will use rdtsc until we have some really fast > (non-syscall) way to have high resolution time diffs.
IIRC, this came up a long time ago WRT Apache, which made a lot of gettimeofday() calls. Someone (Linus?) proposed the solution of a 'magic page' which holds information like gettimeofday() stuff, but could be handled much more rapidly than a standard syscall.
-- Jeff Garzik | Building 1024 | The chief enemy of creativity is "good" sense MandrakeSoft | -- Picasso - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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