In message <20040318135354.GA11739@cs.uni-bonn.de>, Ignatios Souvatzis writes:
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>On Thu, Mar 18, 2004 at 01:11:34PM +0100, Marton Fabo wrote:
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>> A-ha! What are the consequences if I reduce that amount?
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>The find free blocks algorithm of the file system gets slow on average
>if the disk is too full; that's why there _is_ this reserve in the first=20
>place. Read the technical papers about the ffs design if you want the
>details.

Has anyone revalidated those numbers for modern disks?  When FFS first 
came out, there was a lot of talk about rotational optimizations, 
staying within the cylinder, etc.  Nowadays, of course, that's all 
mythical.  

		--Steve Bellovin, http://www.research.att.com/~smb