Horton

Re: [HACKERS] sorting big tables :(

Tom Samplonius <tom@sdf.com>

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From: Tom <tom@sdf.com>
To: The Hermit Hacker <scrappy@hub.org>
Cc: Bruce Momjian <maillist@candle.pha.pa.us>, mimo@interdata.com.pl, hackers@postgresql.org
Date: 1998-05-20T16:42:13Z
Lists: pgsql-hackers 
On Wed, 20 May 1998, The Hermit Hacker wrote:

> 	One of the things that the Unix FS does is auto-defragmenting, at
> least the UFS one does.  Whenever the system is idle (from my
> understanding), the kernel uses that time to clean up the file systems, to
> reduce the file system fragmentation.

  No, that doesn't happen.  The only way to eliminate fragmentation is a
dump/newfs/restore cycle.  UFS does do fragmentation avoidance (which is
reason UFS filesystems have a 10% reserve).

Tom