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From: pnr@planet.nl (Paul Ruizendaal)
Subject: [TUHS] Unix with TCP/IP for small PDP-11s
Date: Tue, 23 May 2017 13:35:02 +0200	[thread overview]
Message-ID: <12C21350-E009-46A8-B50F-76D2AA6A8CF7@planet.nl> (raw)


>> There are two other routes to TCP/IP on a PDP11 without split I/D:
>> ...
>> DCEC's adaptation of the Wingfield TCP/IP library, designed to work
>> with V6. It is mostly a user space daemon, but requires some kernel
>> enhancements.
> 
> I wonder what the performance would be like, since the TCP is in a user
> process (a different one from the application), i.e. there's a process switch
> every time the application goes to send or receive data. This wouldn't have
> been such an issue when the code was written, since ARPANet-type networks
> were not very fast, but with a better network, it would have been limiting.

IEN98 (http://www.rfc-editor.org/rfc/ien/ien98.txt, page 2) has the answer: about 10kb/s.

The DCEC version used shared memory instead of rand ports and was claimed to be
a bit more performant, but I have no number. I'd be surprised if it was twice as fast,
so perhaps 15kb/s.

Paul



             reply	other threads:[~2017-05-23 11:35 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-05-23 11:35 Paul Ruizendaal [this message]
  -- strict thread matches above, loose matches on Subject: below --
2017-05-24 15:21 Noel Chiappa
2017-05-24 17:19 ` Jeremy C. Reed
     [not found] <mailman.1.1495591202.25149.tuhs@minnie.tuhs.org>
2017-05-24  9:20 ` Paul Ruizendaal
2017-05-23 13:43 Noel Chiappa
2017-05-23  1:33 Noel Chiappa
2017-05-23  1:14 Noel Chiappa
2017-05-22  9:28 Paul Ruizendaal
2017-05-22 14:09 ` Clem Cole
2017-05-22 14:51   ` Steve Simon
2017-05-22 16:29     ` Clem Cole
2017-05-22 16:35       ` Ron Natalie
2017-05-22 22:07       ` Paul Ruizendaal
2017-05-22 23:25         ` Clem Cole
2017-05-23  0:36           ` Paul Ruizendaal
     [not found] <mailman.1.1495245601.20449.tuhs@minnie.tuhs.org>
2017-05-20 10:46 ` Johnny Billquist
2017-05-20 17:39   ` Henry Bent
2017-05-20 20:40     ` Johnny Billquist
2017-05-20 20:44       ` Henry Bent
2017-05-20 18:18   ` Warner Losh
2017-05-20 19:05     ` arnold
2017-05-20 20:29       ` Warner Losh
2017-05-20 21:41       ` David Arnold
2017-05-20 21:59         ` Erik E. Fair
2017-05-20 20:40     ` Johnny Billquist
2017-05-20 21:05       ` Warner Losh
2017-05-20 21:34         ` Johnny Billquist
2017-05-21  5:13           ` Random832
2017-05-21 11:04             ` Ron Natalie
2017-05-19 15:15 Noel Chiappa
2017-05-19 16:29 ` Henry Bent
2017-05-19 19:04   ` Ron Natalie
2017-05-20  0:15     ` Warner Losh
2017-05-20  0:21       ` Warner Losh
2017-05-19 17:39 ` Clem Cole
2017-05-21 16:16   ` Dave Horsfall
2017-05-21 19:58     ` Clem Cole
2017-05-21 20:57       ` Ron Natalie
2017-05-21 21:26         ` Clem Cole
2017-05-21 21:46         ` William Pechter

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