Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.toronto.edu!ietf-nntp-distribution-owner
Date: Tue, 25 Jun 1991 15:14:04 -0400
From: Jim.Thompson@Central.Sun.COM (Jim Thompson)
Message-ID: <9106251914.AA05557@neuromancer.Central.Sun.COM>
Original-To: rsalz@bbn.com, tytso@athena.mit.edu
Subject: Re: NEWNEWS
Original-Cc: ietf-nntp@turbo.bio.net, lear@turbo.bio.net, sob@tmc.edu
Newsgroups: list.ietf-nntp
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	From: tytso@ATHENA.MIT.EDU (Theodore Ts'o)
	
	   From: Rich Salz <rsalz@bbn.com>
	   Date: Tue, 25 Jun 91 11:28:35 EDT
	
	   With the proper set of indices, NEWNEWS becomes as cheap as just about
	   any other command.
	
	Yes, but in the implementation which probably over 90% of the NNTP sites
	run, NEWNEWS is done by opening the history file, reading it out line by
	line, and performing a ngmatch() on each one.  When your history file is
	12 meg, and 230k lines, this is nontrivial.
	
This is likely due to the fact that the code that R$ mentions is 
not commonly available (yet), rather than reluctance by a large number
of sites to innovate.  

If your newsreaders, or feeding arangements, need such indices, then
you'll likely find the software and install it.

Jim