Re: 2.6.24-rc1: First impressions

[Bill Davidsen]

Andrew Morton wrote:
> On Fri, 26 Oct 2007 21:33:40 +0200
> Ingo Molnar <mingo@xxxxxxx> wrote:
>
> > * Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:

> > so a final 'sync' should be added to the test too, and the time it takes 
> > factored into the bandwidth numbers?
>
> That's one way of doing it.  Or just run the test for a "long" time.  ie:
> much longer than (total-memory / disk-bandwidth).  Probably the latter
> will give a more accurate result, but it can get boring.
Longer might be less inaccurate, but without flushing the last data you 
really don't get best accuracy, you just reduce the error. Clearly doing 
fdatasync() is best, since other i/o caused by sync() can skew the results.

--
Bill Davidsen <davidsen@xxxxxxx>
  "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot

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