Path: utzoo!attcan!uunet!lll-winken!ames!hc!lanl!beta!ttp
From: ttp@beta.lanl.gov (T T Phillips)
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: Is uncompression faster than disk I/O?
Summary: Compression for speed up of file access
Keywords: compress zoo arc I/O speed
Message-ID: <23240@beta.lanl.gov>
Date: 19 Jan 89 17:04:45 GMT
References: <14227@princeton.Princeton.EDU>
Organization: Los Alamos National Laboratory
Lines: 20

In article <14227@princeton.Princeton.EDU>, nr@notecnirp.Princeton.EDU (Norman Ramsey) writes:
> 
> Someone suggested to me that it might pay off to store my data files
> in compressed format, then uncompress them when I get ready to use
> them.  ... has anybody substantiated this
> claim for IBM PC, XT, AT, or PS/2  

I have found that some times this is true, other times not.  In
working with Turbo C on a Kaypro 2000 portable with one of the
slowest 3.5" floppy drives ever created, I found that it was
several times faster to ARChive the .H files, and then extract
them to a RAM disk for use than it was to copy the individual
files over to the RAM disk.  This was a case with a lot of
little files, where the time spent accessing the directory
between reads really slowed down the file by file copy.  On the
same machine working with some of the large files like the
libraries for Turbo C, the ARC overhead slowed things down.  I
never tried options like ARCing the files in an uncompressed
format.  Incidentally, I was using a pretty old and now probably
illegal version of pkxarc.