On Mon, Sep 22, 2003 at 02:43:40PM -0400, [EMAIL PROTECTED] wrote:
...
> But now I noticed that my application is occassionally doing slower
> iterations. Average iteration time used to be 0.2 ms without polling
> enabled. With the device polling changes, the average time is still around
> the same, but once every few minutes the application sees iterations that
> are 3.3 seconds (*seconds*, not a typo) long.
most likely your application makes some assumptions on the duration of
a clock tick and then it gets confused when, say, a select returns
quicker, or some time difference becomes negative, etc. etc. because
of the finer granularity.
very common type of bug.
cheers
luigi
> This seems to happen as soon as I use the kernel with HZ=1000. Enabling or
> disabling device polling does not seem to make any difference to this
> behavior. I am trying to understand why there seem to be a few really long
> iterations. Could it happen that the application does not get any CPU for
> that long? Seems very counter intuitive that higher HZ should cause this.
>
> Could anyone shed any light on what is happening ?
>
> Thanks,
> -ansh
>
> --------------------------------------------------------------------
> mail2web - Check your email from the web at
> http://mail2web.com/ .
>
>
> _______________________________________________
> [EMAIL PROTECTED] mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-hackers
> To unsubscribe, send any mail to "[EMAIL PROTECTED]"
>
_______________________________________________
[EMAIL PROTECTED] mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-hackers
To unsubscribe, send any mail to "[EMAIL PROTECTED]"
