-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Julian Elischer wrote:
> Krassimir Slavchev wrote:
>
>>
>> Also, I am able to set HZ=100000 but the thread switching time is still
>> ~1ms.
>
> You must be talking about the time that a thread can run before it is
> pushed out by other threads? I know I've seem many x 10,000 context
> switches in some cases, i.e. look at very high interrupt rates
> etc. so I guess I'm not sure what you are measuring..
>
> at one time the scheduling quantum was independent of Hz.
> I am not sure how true that is now..
>
The scheduling quantum is independent of Hz for Hz > 1000.
usr/src/sys/kern_tc.c:
...
if (hz > 1000)
tc_tick = (hz + 500) / 1000;
else
tc_tick = 1;
...
I am not sure whether setting Hz > 1000 impact on performance or not,
e.g using polling(4).
Removing this limitation and setting kern.hz=10000 give 100usec quantum.
Thanks for the point.
Best Regards
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (FreeBSD)
iD8DBQFJDt1JxJBWvpalMpkRAnWCAJ9z5Z7JYDC/3AdsJe+Cn7+dg6y3HwCdHPZA
6sK5dec43n41/QcbiluJoeA=
=8u2E
-----END PGP SIGNATURE-----
_______________________________________________
freebsd-performance@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-performance
To unsubscribe, send any mail to "[EMAIL PROTECTED]"
