BogoMIPS no longer supported on PowerPC?

Li Yang-r58472 LeoLi at freescale.com
Wed Aug 23 20:55:26 EST 2006


Ok, I rephrase my question as is it no longer needed?  Sometimes people
may use this value as a rough estimation of CPU performance.  There are
people even maintained a list of bogoMIPS of most CPUs.  Maybe it is
still needed for some legacy reasons.  I'm not very sure.  :)   At leave
we need to inform people who do look at this magic number and find it
amazingly low.

Best Regards,
Leo
> -----Original Message-----
> From: Johannes Berg [mailto:johannes at sipsolutions.net]
> Sent: Wednesday, August 23, 2006 6:38 PM
> To: Li Yang-r58472
> Cc: linuxppc-dev at ozlabs.org
> Subject: Re: BogoMIPS no longer supported on PowerPC?
> 
> On Wed, 2006-08-23 at 18:25 +0800, Li Yang-r58472 wrote:
> > I noticed a recent modification to __delay has changed from using
empty
> > loops to reading timebase.  Thus, breaks the calculation of
bogomips,
> > and makes it terribly low.  Is the bogomips no longer being
supported on
> > powerpc arch?
> 
> What's there to be 'supported'? The only purpose of bogomips is
> calibrating the delay loop, and that has changed now by using
timebase,
> hence bogomips no longer have a purpose. There was even a patch to
> remove it from /proc/cpuinfo but I'm not sure whether that got applied
> or not.
> 
> johannes



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