question about mksnap_ffs and NFS interaction

[Alan Horn]

Folks,

I have some NFS exported filesystems (home directories) that I'm placing 
under snapshots.

Timing of making a snapshot on a 140GB filesystems running about 90% full 
takes about 17 seconds.

Given that these filesystems are fairly heavily used homedir filesystems, 
what is the expected impact of those 17 seconds on NFS clients.

My guess is that its enough to be seen but not enough to cause NFS 
timeouts. So far I've been scheduling snapshots for the middle of the 
night, but I'd like to start doing four per day. Does anyone have any data 
on the likely impact ?

Please reply direct to me as I'm not subbsed to the list.

Cheers,

Al