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From: Bakul Shah <>
To: Dan Cross <>
Cc: John Cowan <>, ron minnich <>,
	COFF <>
Subject: [COFF] Re: [TUHS] Re: the wheel of reincarnation goes sideways
Date: Sat, 11 Mar 2023 15:28:08 -0800	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

On Mar 9, 2023, at 11:55 AM, Dan Cross <> wrote:
> 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. All of that would consume some amount of RAM (though
> there'd be a lot of sharing of text and read-only data and so on),
> some VM space requiring RAM for paging structures and so on, some
> accounting data in the kernel, 1000 pseudo-ttys allocated, entries in
> the process table, etc. But, most of those shells would spend most of
> their time blocked waiting on input, so wouldn't consume CPU
> continuously, and similarly with the TCP connections mostly idle, the
> kernel is not generally wasting a lot of processor time on the login
> sessions. There'd be some bookkeeping data on disk, but that would be
> small. System overhead would amount to maybe a few megabytes, I'd
> imagine.

Not the same but in 1995 at Real Networks our server s/w running on
a 50Mhz or 100Mhz Pentium could handle 1000 TCP control connections
(mostly idle) and 1000 UDP "streams", each sending 10 packets/second,
which was the limiting factor. IIRC we had reduced per socket tcp
send/recv buffer size to a small number. I don't recall now whether
these machines had more than 16GB but we didn't want to tie up lots
of memory in idle buffers.

We got a real boost in traffic in Oct'95 when people all over the
world wanted to know the verdict in O.J.Simpson's murder trial in
real time! After that I added code for feeding live streams to any
downstream servers so that theoretically a 3 level distribution
tree can deliver live data to a billion people.

  parent reply	other threads:[~2023-03-11 23:28 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <>
2023-03-08 19:52 ` [COFF] Re: [TUHS] " Dan Cross
2023-03-08 20:18   ` [COFF] " Tom Ivar Helbekkmo via COFF
2023-03-09  1:22   ` [COFF] Re: [TUHS] " John Cowan
2023-03-09 19:55     ` Dan Cross
2023-03-09 20:09       ` Larry McVoy
2023-03-11 20:32         ` Dan Cross
2023-03-11 23:28       ` Bakul Shah [this message]
     [not found]   ` <>
2023-03-13 22:34     ` Dan Cross
2023-07-05 21:48       ` Dan Cross
2023-07-05 23:58         ` Grant Taylor via COFF
2023-07-06  1:02           ` Dave Horsfall
2023-07-06 16:47             ` Grant Taylor via COFF
2023-07-06  2:35           ` Dan Cross
2023-07-06  4:18           ` Robert Stanford via COFF
2023-07-06 16:53             ` Grant Taylor via COFF
2023-07-06 17:54               ` Adam Thornton
2023-07-09 14:55           ` Michael Parson
2023-08-01  9:52             ` Michael Cardell Widerkrantz
2023-08-01  9:49         ` Michael Cardell Widerkrantz
2023-08-01 15:55           ` Dan Cross
2023-08-01 16:27             ` Grant Taylor via COFF
2023-08-02 16:07               ` Dan Cross
2023-08-02 20:58                 ` Grant Taylor via COFF
2023-08-02 21:16                   ` Dan Cross

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