Quick question.

Wed Aug 4 06:48:59 UTC 2004

On Tue, 3 Aug 2004, Alexei Roudnev wrote:

> In theory, yes. On pracrtice, 2 CPU improve behavior dramatically.

That is not about reliability. That's to do with software 
performance.

I was purely picking a, admittedly pedantic, nit with the notion that 
SMP == more reliable. I'm not trying to argue that SMP does not have 
other benefits (eg performance).

> 4 CPU makes system too complex (as you wrote beloow).

Nah, the big jump in complexity appears to be from no-concurrency to 
concurrency. After that initial hurdle, 2 to 4 to 8 CPUs isnt as big 
a deal (making it scale is though).

> New P-IV with multi threading may be a good selection - behave as 2 
> CPU system but is not so complicated as SMP.

>From the OS POV, the complication is the same. And yes, even 
single-processors are today capable of presenting multiple execution 
contexts to software, and it seems to be a trend we'll see more and 
more of.

> In reality, applications are less reliable on 2 CPU systems (if 
> they have some kinds of bugs, which make sense on SMP only), so I 
> agree with you in some cases.

Right..

regards,
-- 
Paul Jakma	paul at clubi.ie	paul at jakma.org	Key ID: 64A2FF6A
Fortune:
Rubber bands have snappy endings!