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Date: Tue, 10 May 2005 15:30:40 +0200
From: Divacky Roman <xdivac02@stud.fit.vutbr.cz>
To: Siddharth Aggarwal <saggarwa@cs.utah.edu>
Message-ID: <20050510133040.GA98680@stud.fit.vutbr.cz>
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cc: freebsd-hackers@freebsd.org
Subject: Re: ffs snapshots
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On Mon, May 09, 2005 at 09:43:02AM -0600, Siddharth Aggarwal wrote:
> 
> Hi,
> 
> I was wondering why the limit for file system snapshots in BSD 5 has been 
> set to 20. Is it a limitation due to the way this feature has been 
> implemented? 

use the force, read the source ;)

/*
 * The maximum number of snapshot nodes that can be associated
 * with each filesystem. This limit affects only the number of
 * snapshot files that can be recorded within the superblock so
 * that they can be found when the filesystem is mounted. However,
 * maintaining too many will slow the filesystem performance, so
 * having this limit is a good idea.
 */
#define FSMAXSNAP 20