mksnap_ffs takes 4-5 minutes?

[Skylar Thompson]

On Tue, Jul 19, 2005 at 03:38:03PM -0500, Eric Anderson wrote:
> Last week, I tried making a snapshot of one of my NFS servers' 
> partitions.   I've done this one other machines before, with smaller 
> barely used partitions, and it has always been relatively snappy.
> 
> This time, when I ran mksnap_ffs, the command took nearly 5 minutes, in 
> which time all NFS traffic was suspended, as well as all disk access on 
> the machine.  After reading in the FreeBSD Implementation book 
> (McKusick), it claims it should be very very fast.
> 
> Anyone know why it should take so long to do this snapshot?  Is this 
> expected normal behaviour, or should I expect faster snapshots?
> 
> Here's some info on the filesystem:
> Filesystem        1K-blocks     Used     Avail Capacity iused    ifree 
> %iused  Mounted on
> /dev/da1s1d       406234604 91799154 281936682    25% 1300303 51197103 
>   2%   /scr03
> 
> /dev/da1s1d on /scr03 (ufs, NFS exported, local, soft-updates)

Does that filesystem have a lot of open files? I believe all busy inodes
have to be copied in the snapshot process.

-- 
-- Skylar Thompson (skylar at cs.earlham.edu)
-- http://www.cs.earlham.edu/~skylar/
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