[COFF] [TUHS] Re: the wheel of reincarnation goes sideways

[Larry McVoy]

On Thu, Mar 09, 2023 at 02:55:44PM -0500, Dan Cross wrote:
> On Wed, Mar 8, 2023 at 8:22???PM John Cowan <cowan at ccil.org> wrote:
> > On Wed, Mar 8, 2023 at 2:53???PM Dan Cross <crossd at gmail.com> wrote:
> >> But the
> >> 3090 was really more like a distributed system than the Athlon box
> >> was, with all sorts of offload capabilities. For that matter, a
> >> thousand users probably _could_ telnet into the Athlon system. With
> >> telnet in line mode, it'd probably even be decently responsive.
> >
> > I find that difficult to believe.  It seems too high by an order of magnitude.
> 
> I'm not going to claim it would be zippy, but I do think it would work
> acceptably.
> 
> Suppose that 1000 users telnet'ed into the x86 machine, but remained
> essentially idle; what resources would that consume? We'd have 1000
> open TCP connections, a thousand shell processes, a thousand
> telnetd's, etc. 

The early Unix code really did not like stuff like this.  Lots of linear
scans through what were assumed to be short lists.  I still remember an
SGI Challenge being brought to it's knees by a bunch of racks of modems.
The same machine could move a ton of data but not when it was being
forced through a zillion sockets.

Linux seems well past that problem but it's possible that back in the
Athlon days it still sucked.  I pinged Linus, if he remembers when the
kernel got taught to scale on sockets I'll report back.

--lm