*BSD News Article 70662


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From: Vlad <roubtsov@uiuc.edu>
Newsgroups: comp.unix.bsd.misc
Subject: Q: fast file system
Date: Tue, 11 Jun 1996 13:16:23 -0500
Organization: Baphomet's Throne
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Hi:
	In fact I have 2 questions:

(1) Is is true that only files without indirect blocks can have the last
bit allocated in a fragment ?

(2) If it's correct to say that block pointers in the inode structure
point to blocks (not fragments) and distinct fragments within the same
block can be allocated to different files, then how does the file system
determine which fragments in a given fragmented block belong to which
file ? I mean I understand that free block bitmaps have granularity on
the fragment level, but that's not enough: there must be a way to
specify that, say, first 3 1024-fragments in a 4096-block belong to this
file associated with this inode and the last 1024-fragment belongs to
that file/inode...etc.

Please help clarify my confusion,
Vlad.
-- 
До