Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!cs.utexas.edu!uunet!munnari.oz.au!mtiame!ubeaut!ubeaut!chris
From: chris@ubeaut.enet.dec.com (Chris Jankowski)
Newsgroups: comp.sys.pyramid
Subject: Re: limit on telnet sessions
Message-ID: <1991Jun7.043421.13811@ubeaut.enet.dec.com>
Date: 7 Jun 91 04:34:21 GMT
References: <1991Jun5.180245.19975@geac.com>
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Organization: Digital Equipment Corporation
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In article <1991Jun5.180245.19975@geac.com> you write:
>Can anyone tell me the absolute maximum number of incoming telnet
>sessions on an MIS-4 (8540) and/or MIS-12 (8580) with a single TPE
>interface?  I know this is probably buried in a manual someplace,
>but I can't find it.  Is it limited by the number of pseudo ttys
>that can be defined, or something else?
>

2048 if memory serves me right.
You need to generate those ptys (probably by hand).
(You may also try to use /etc/makeptys or something such, but it used to
be buggy above 128 ptys).

>I'm also interested in practical limits on the number of users that
>can be connected to an Ethernet network.  I realize that would
>likely be expressed as a function of the traffic generated by
>each user, plus other factors.  I'd be interested in hearing about
>any real life experience that you'd like to share.

The largest number of logged in telnet users I have seen on a Pyramid was
about 530. 

There is really no hard limit on a *bridged* Ethernet network other than
Ethernet addressing capability which is in the order of 2**48, which
should be sufficient I think (:-).

When you add more load to your Ethernet the response time will
suffer but the network will stay up.
(I am talking here about a bridged Ethernet with bridges of finite
throuput and reasonable topology.)

However if your users are actually doing something on a single large
host it is likely that at some point they will saturate a resource
on the host and from this point onwards adding more users will
cause a very quick deterioration in response time.
 
Speaking for myself only, etc...

 +-+-+-+-+-+-+-+ Chris Jankowski - Open Systems Eng.- chris@ubeaut.enet.dec.com
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