ftp runs slower on CPU 1

[Oliver Fromme]

Phungte <phungte at xxxxxxxxx> wrote:
 > I am running a performance test on a dual cpu machine, with DragonFly
 > 1.3.7-DEVELOPMENT #2.
 > The machine runs as ftp server.
 > When ever the tcp thread runs on CPU0, the speed of the transfer is
 > ~90MB/sec.
 > If the tcpu thread runs on CPU1, the speed is down to less than 40MB/sec.

My guess is that interrupts are serviced on one CPU only.
If your server process happens to run on the same CPU, it
has to share it with interrupt processing.  If it runs on
the other CPU, then it gets its performance exclusively.
It would be interesting how enabling or disabling polling
influences your results.

(Disclaimer:  I'm not a DF kernel hacker, so I'm sure some-
one will correct me.  :-)

Best regards
   Oliver

-- 
Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
Dienstleistungen mit Schwerpunkt FreeBSD: http://www.secnetix.de/bsd

Any opinions expressed in this message may be personal to the author
and may not necessarily reflect the opinions of secnetix in any way.