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Date: Sun, 16 May 2004 12:04:41 -0500
From: Dan Nelson <dnelson@allantgroup.com>
To: Scott Long <scottl@freebsd.org>
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cc: Michael Hamburg <hamburg@fas.harvard.edu>
Subject: Re: fsck in -current
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In the last episode (May 16), Scott Long said:
> Actually, bgfsck unconditionally inserts a delay into every 8th i/o
> operation to try to keep from saturating the disks.  Unfortunately
> this isn't terribly sophisticated and it results in bgfsck taking an
> eternity whether the system is idle, loaded, or reniced.

See http://dan.allantgroup.com/FreeBSD/fsck_ffs.diff for a patch that
removes the delay if it's at the minimum value, and more fairly
calculates disk wait time.  This cuts bgfsck time from ~4 hours to 20
minutes on my 36gb /usr.

-- 
	Dan Nelson
	dnelson@allantgroup.com