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From: mac@olduvacs.cs.virginia.edu (Alex Colvin)
Newsgroups: comp.os.research
Subject: Re: File system design & fragmentation
Message-ID: <6956@saturn.ucsc.edu>
Date: 22 Apr 89 15:02:57 GMT
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> 1) I am looking for references regarding file system design. In
> particular, how to manage the problem of fragmentation, something that
> doesn't seem to be covered in the OS textbooks that I've referenced.

See acm Trans. on Computer Systems 5(4) Nov. 87
PDL Koch "Disk File Allocation Based on the Buddy System".

A mostly extent-based file system which uses background compaction to reduce
fragmentation.  Files tend to a few large extents which can be transferred
in few I/O commands.  This lets the system use more of the disk channel
bandwidth, instead of waiting around for interrupt service.