[1782] in linux-scsi channel archive
Re: Ppro 180 or p200 or dual p166??
daemon@ATHENA.MIT.EDU (Ben Scott)
Wed Apr 30 23:07:15 1997
Date: Wed, 30 Apr 1997 23:05:10 -0400 (EDT)
From: Ben Scott <bscott@leonardo.sr.unh.edu>
To: Robert Johannes <rjohanne@piper.hamline.edu>
cc: linux-scsi <linux-scsi@vger.rutgers.edu>
In-Reply-To: <Pine.SOL.3.96.970430204235.20305A-100000@mendeleev>
On Wed, 30 Apr 1997, Robert Johannes wrote:
> Although this is not a scsi related question, it has to do with system
> performance.
So you posted it anyway? :)
> I'm trying to upgrade my cpu and I have come across three interesting
> choices that all seem reasonably priced; I mean all of the cpus I'm
> mentioning below will cost within 40 dollars of each other. Here's my
> question; on my system which I use for composing and recording music and
> video clips, some times there are unexplained hangs;
Do you have an all SCSI system? If not, consider moving to all SCSI with
good components. IDE has various short-coming that often get in the way of
intense disk I/O, especially with multiple devices running at once. If you do
have a SCSI system, what kind of card? Does it support busmastering under
Linux? If not, you might want to consider a better card, it will help. Also
check to see if SCSI bus disconnects are supported for that card. SCSI bus
disconnects allow a device (eg, CD writer) to "disconnect" from the SCSI bus
to do its thing, while another device (eg, hard drive) can continue to pump
data to the system. Another thing I've seen mess up at least one system is
"tagged command queuing", try shutting that off just to see how it reacts.
> I'm in the middle of both playing and recording at the same time, the
> system will just freeze so that I'm unable to stop the recording or the
> playing or even to move the mouse.
Sounds like a SCSI bus hang. Have you checked cables, termination, that
sort of thing? Maybe your SCSI bus is too long? Try taking unneeded devices
out of the chain and testing with the basics to do what is causing the
problem. Maybe try changing device order. If you can, swap devices with
another computer. Try and find the fault.
> My first understanding of the freeze when I'm doing simultaneous record
> and play is that the cpu I have (pentium 166) isn't good enough to handle
> multiple tasks which are that intensive,
Depends on system board, kernel and driver versions, SCSI card, SCSI
devices, SCSI driver options, other devices in the system, and a few million
other things. :) But, in general, what you describe shouldn't be *too* big a
deal for a P5/166. If possible, shutdown X and try it with just a text-mode
screen, sometimes X can cause problems or use too much RAM and/or CPU.
> used while I'm doing these apps. As for the fatal error at address ..., I
> don't know what that means; I wish I could remember the address,
Did you check /var/log/messages and related files?
> My conclusion is that I need to get a new cpu and mother board (it is not
> just these experiences which have persuaded me) and I'm trying to decide
> between a dual pentium 166, a pentium 200 a cyrix p200+ or a pentium pro
> 180.
Linux, being a 32-bit OS, likes a PPro better then a Pentium. On the other
hand, dual CPUs is real nice, not just because you have twice the CPU, but
because the system can do two things at the *exact* same time. Normally, when
the kernel has to do something, everything else halts. A P5/200 vs P6/180, I
would go with the P6/180. Dual P5 vs single P6, I dunno, tough decision. I
have no experience with the Cyrix, sorry, but I've found sticking with "the
leader" can sometimes eliminate problems.
Make sure your case has good cooling for all your new and old hardware. :)
----
Ben Scott <bscott@leonardo.sr.unh.edu>
Technical support staff
Space Science Center
University of New Hampshire
