Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!cbmvax!vu-vlsi!dsinc!syd
From: syd@DSI.COM (Syd Weinstein)
Newsgroups: news.software.b
Subject: Re: How do articles get in the wrong order?
Message-ID: <1989Sep11.134953.20655@DSI.COM>
Date: 11 Sep 89 13:49:53 GMT
References: <5200@looking.on.ca> <66812@uunet.UU.NET> <1989Sep7.151826.11816@i88.isc.com> <3919@hplabsz.HPL.HP.COM> <10478@looking.on.ca>
Reply-To: syd@DSI.COM
Organization: Datacomp Systems, Inc.  Huntingdon Valley, PA
Lines: 33

brad@looking.on.ca (Brad Templeton) writes:

>It might be useful to list the ways in which articles can get in the wrong
>order.

>There are three classes of such problems:

>	b) They are transmitted to you in the wrong order from a machine
>	   that got them in the right order
>B)	This one's hard to figure.  Normally uucp and other transport mechs
>	send stuff in the order they got it, unless their sequence numbers
>	wrap around.  There might be problems caused by interrupted
>	transmissions or people who move news at different priorities.

>	Cross posting on a followup article that's not on the original can
>	allow the followup to take a higher priority path, but this is rare.
Actually this is the most common and hardest to fix.  Many UUCP's decide
what to do by sequentially reading the directory for jobs to process.
Now entries in the directory are not assigned sequentially by id, but
in the next available hole.  As a site processes uucp jobs, the holes
open up and batching fills them, thus later batches could easily
go out earlier than their predicessors.  This is especially true
if a site picks up news less often that the sending site batches
it.

Since most people run binary copies of UUCP, fixing this one would 
be tough,  the only cure is to have uucp process them in queue order
not directory order and uucp doesn't do that unless you fix the source.
-- 
=====================================================================
Sydney S. Weinstein, CDP, CCP                   Elm Coordinator
Datacomp Systems, Inc.				Voice: (215) 947-9900
syd@DSI.COM or {bpa,vu-vlsi}!dsinc!syd	        FAX:   (215) 938-0235