Performance of 4.x vs 5.x (Re: Lifetime of FreeBSD branches)

Kris Kennaway kris at
Wed May 25 15:37:23 PDT 2005

On Wed, May 25, 2005 at 03:33:39PM -0700, Jon Dama wrote:
> Could this be quantified by setting up a synthetic experiement:
> 1) one machine uses dummynet to generate a uniform packet/sec stream
> 2) another machine has a process receiving those packets and recording
>    their arrival relative to the local TSC.  afaik, the TSC is the only
>    source of wall-time that doesn't involve a system call.  Is that right?
>    Are the TSCs synchronized on SMP systems?
> 3) Generate another source of activity on the receiving machine to
>    estimate the effect of PREEMPTION relative to the (lack of) quiescence.
> 4) use the jitter in the TSC deltas to infer the effect of preemption

That would be attempting to benchmark something entirely different.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url :

More information about the freebsd-stable mailing list