some uucp transfer rates for 3b1 w/ telebit

DoN Nichols dnichols at ceilidh.beartrack.com
Thu May 30 08:42:56 AEST 1991


In article <1789 at hico2.UUCP> kak at hico2.westmark.com writes:
>
>In around 107 somewhat related articles, several authors discuss
>Hardware Flow Control, telebits, and throughput.
>
>I thought I'd add some transfer statistics from hico2,
>a 3b1 with starlan (low option), serial patch, HDB uucp,
>and a Trailblazer Plus (4.0 roms), using uucp spoofing
>and locked 19200 interface speed.
>
>What I did was look at the files /usr/spool/uucp/.Adm/xferstats
>and /usr/spool/.Old/xferstats, edit out irrelavant information,
>and then throw out data on very short transfers ( < 3 seconds ),
>or slow transfers ( < 1000 bytes/sec ).  I've ordered the remaining
>entries from faster to slowest.

	But, the slow transfers are a symptom of the problem we've been
discussing!  They result from lost data forcing a timeout and a resend of
the affected packet.  What percentage of the whole was the collection of
slow transfers?

	[ ... ]

>I suspect that a 3b1 can send faster than it can receive.

	That, I believe, has been the general concensus of the discussion.

>Assuming that these numbers are realistic, and
>at least somewhat meaningful,
>it's at least POSSIBLE to get good throughput.
>
>For what it's worth, here it is:
>

	[ ... acres of statistics trimmed out ]

	I found that, at least with the ethernet enabled, the very slow
entries more than ate up the gain by running at 19200 instead of 9600.  (It
also usually ended in a timeout and failure of the transfers, if there was
more than one package of news waiting to come to my machine.  Also, when I
tried the 'e' protocol, at 9600, outgoing packets improved, while incoming
ones failed with the ethernet enabled.  I didn't bother trying it with the
ethernet disabled, since I no longer run that way.  (News comes into the
3b1, I am using a Sun 2/120 as a terminal via ethernet.  Love those 80x65
xterm windows.


-- 
Donald Nichols (DoN.)		| Voice (Days):	(703) 664-1585
D&D Data			| Voice (Eves):	(703) 938-4564
Disclaimer: from here - None	| Email:     <dnichols at ceilidh.beartrack.com>
	--- Black Holes are where God is dividing by zero ---



More information about the Comp.sys.3b1 mailing list