Date: Sat, 2 May 1998 09:00:02 -0700 (PDT) From: Matthew Dillon <dillon@backplane.com> To: freebsd-bugs@FreeBSD.ORG Subject: Re: i386/5398 Message-ID: <199805021600.JAA18422@freefall.freebsd.org>
index | next in thread | raw e-mail
The following reply was made to PR i386/5398; it has been noted by GNATS.
From: Matthew Dillon <dillon@backplane.com>
To: John-Mark Gurney <gurney_j@efn.org>
Cc: Poul-Henning Kamp <phk@FreeBSD.ORG>, freebsd-gnats-submit@FreeBSD.ORG
Subject: Re: i386/5398
Date: Sat, 2 May 1998 08:58:15 -0700 (PDT)
:> State-Changed-Why:
:> I think your machine simply is out of steam. Blitting 3 mbyte around is
:> going to take quite a bit of your cpu and bus bandwidth.
:
:actually, this is probably due to a device that isn't with-in the spec'd
:rs-232 speeds... I have the same problem with the ricochet on my
:notebook... I can't run faster than 19.2kbps because the ricochet runs
:about 5% over the 19.2kbps clock (I get about 2050int/sec at 19.2kbps)..
:
:try running the speeds lower...
Ahh.... nonsense. Unless the serial port is out of sync more then 1/2
bit time every 10 bits, the 16x oversampling done by the 16xxx has no
problem dealing with this issue. Also since the problem is demonstratably
related to the hardware FIFO's water marks, it obviously has nothing to
do with synchronous/frequency/clock problems and just as obviously has
everything to do with interrupt latencies.
cpu out of suds? This is a pentium pro 200. More likely, there is a
serious interrupt disablement latency somewhere in the kernel.
-Matt
:--
: John-Mark Gurney Modem Rev/FAX: +1 541 346 9237
: Cu Networking P.O. Box 5693, 97405
:
: Live in Peace, destroy Micro$oft, support free software, run FreeBSD
: Don't trust anyone you don't have the source for
:
Matthew Dillon Engineering, BEST Internet Communications, Inc.
<dillon@backplane.com>
[always include a portion of the original email in any response!]
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-bugs" in the body of the message
help
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199805021600.JAA18422>