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Re: SGI



>Well, it depends what server you're talking about.  Demanding does not
>necessarily mean 'HUGE'.  

By "Huge" I ment a very sizable number of people feeding off your web site,
you know, like microsoft.com, yahoo.com, etc.  Then the loads require
things like server clustering, etc. because it goes beyond the realm of one
machine --for performance and reliability issues.

>On one of my Suns there are currently over
>100 processes running, including +-30 httpd's, up to 50 sendmails
>(actually exim) at a time, about 20 other assorted daemons (NFS,
>automount, ntpd, named, vold, etc.), several cron jobs per hour,
>various CGI scripts, Macintosh Application Environment (a virtual
>Mac), all the usual underlying Unix processes, 

Well, yes, but how many of those processes are really consuming significant
cpu time. If you run the "top" command, how much of a load are they really?
Httpd in particular is pretty much asleep until something is requested of
it.  Even then, there really is very little number crunching going on, it
just reads a text file (OK, and associated images) from disk and pumps them
out the ethernet line.  Without being deeply familiar with the internals of
a particular implementation I'd bet that a good deal of the process
involves a DMA transfer to a memory buffer (no CPU time to speak of) and
subsequent quasi-DMA to the ethernet hardware.  It's not really taxing
until you get into hundreds of simultaneous connections pumping data all
the time.  According to the folks at BSD, a 100 Mhz Pentium running BSD and
X-windows can still saturate a T1 line while being useful as a workstation
(for basic stuff).  
That in contrast to a 3D modelling/rendering application...that's what I
ment by "demanding" in my original post.

Actually, in my opinion, one of the things that makes Unix so powerful is
that all of the neat little hot-rod routines that run out of view are tight
and simple (relatively speaking). They do what they have to do quickly and
get out of the way. In contrast to that the Windows family has a lot of
"fat" code and Macs are even worst.



-Martin Euredjian
 Telecine Engineer - Hollywood Digital
 Head Droid - Ai/Robotics


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