[tor.news] Questions about our UUCP report

henry@utzoo.UUCP (Henry Spencer) (01/09/87)

Dave Sherman asked a few questions about the format of our uucp status
report, and suggested that I might want to post the answers.  Seems
reasonable, so here goes.

> >  1 spectri poll      (oldest 3.0 days)
> 
> mail & news I understand. What is poll? ...

We run our calling system in a slightly more complicated way than some
other sites.  Every hour, we try to call every system for which there
is traffic.  (Of course, some of these calls are blocked by things like
time-of-day restrictions before they get very far.)  There are some
sites that we want to poll regularly, either because they don't call us
or because we want to call them occasionally as a safety precaution against
things like autodialer failures.  This is done by creating spurious traffic
for them:  an empty C. file is enough to convince the software that there
is traffic for that site.  Once the connection is made, uucico looks at
the file for work requests, finds none, does none, decides that the file's
requests have been completed, and removes the file.  That's what a "poll"
item is.  They are listed in our uucp report only if they are old enough
to be suspicious.

The reason behind this slightly involved scheme is that invocations of
uucico can fail for many reasons, such as the line already being in use.
Trying to poll people by just running uucico is thus unreliable.  The
poll-file scheme makes utzoo try every hour until a successful connection
is made, and then stop trying until the next time polling is requested
(or real traffic gets queued).

> And what is class c?

Wups, sorry, for obscure historical reasons some bits of news go out as
class c rather than the normal d, and the reporting program didn't know
about that.  Fixed.

> > alice		2
> 
> 2 what? files transferred? what determines the point at which you
> won't show bytes/seconds = speed?

Yup, just files transferred.  Small transfers -- ones with size or duration
below certain thresholds -- are considered to be too small for reliable
bytes/second calculation and hence aren't counted for that purpose.  If
there was nothing but small transfers, the reporter just reports a count
of them without trying to estimate speed.

> > dciem	 286089/3484	=  82.1  (50.41 - 95.22)
> 
> 50.41 and 95.22 are what? Slowest and fastest speeds for
> transfers of individual files during this period?
> And why do you only show this for some links?

Yes, they're the slowest and fastest speeds.  They're shown only if there
is at least 20% deviation from the average.

> > utcs	 737590/1992	= 370.3  (287.48 - 420.59)
> 
> Wow. 4800 baud direct line? UofTNet? ...

4800-baud direct line.  Some day we will be on the local network, but not
just yet.  We also have a 4800-baud hardwired line to utcsri, but that one
is out of order at the moment and our hardware man is too swamped with
more urgent things to investigate right away.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,decvax,pyramid}!utzoo!henry