Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!watmath!clyde!caip!ll-xn!cit-vax!mangler
From: mangler@cit-vax.Caltech.Edu (System Mangler)
Newsgroups: net.news.b
Subject: Re: Sorting batches helpful?
Message-ID: <764@cit-vax.Caltech.Edu>
Date: Fri, 27-Jun-86 17:19:06 EDT
Article-I.D.: cit-vax.764
Posted: Fri Jun 27 17:19:06 1986
Date-Received: Sat, 28-Jun-86 09:37:10 EDT
References: <510@mecc.UUCP> <2376@phri.UUCP>
Distribution: na
Organization: California Institute of Technology
Lines: 16
Keywords: sort news batch compress
Summary: compress doesn't recognize repetition too well

In article <2376@phri.UUCP>, roy@phri.UUCP (Roy Smith) writes:
> [...] I took one day's worth of news and ran it through batch and
> compress, with and without sorting the filenames.  The sorted batches were
> indeed smaller, but only about 5-10% so. [...]

Roy's article compresses to 70% of its original size.  Two copies
concatenated compresses to 60%.  So even quoting an entire article
doesn't do much to the compression ratio.  Getting a 5-10% better
compression ratio is awfully good, I think.  I guess I'll try Roy's
suggestion of sorting the filenames.

Perhaps the compression ratio is affected more by the size of the
batch than by the degree of repetition... What's the limit on the
size of a batch?

Don Speck	speck@vlsi.caltech.edu