Access to UFS stuck during snapshot.

[Kent Ho]

Hi,

I having problems accessing file system during snapshot runs.  snapshot 
takes approximately 10 to 20 mins to run.

During that time access to files in the file system are blocked until 
the snapshot has completed.  Lot of processes was stuck and piles up on 
the fs.

This fs stores mailboxes and it's accessed 24/7.  This is similar to 
what described in this thread.

http://www.freebsd.org/cgi/getmsg.cgi?fetch=14968+0+/usr/local/www/db/text/2006/freebsd-fs/20060312.freebsd-fs

Has this been improved or fixed in recent releases, I see a bunch of 
fixes in march?  any possible work around?  any alternatives or 
recommendations?  Looking for high availability fs with snapshots.

I'm running:
FreeBSD fs1 5.4-RELEASE FreeBSD 5.4-RELEASE #0: Sun May  8 10:21:06 UTC 
2005     root at harlow.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386
Intel(R) Xeon(TM) CPU 2.40GHz
3ware 9000 series Storage Controller
1GB RAM

I've switched from netapp to Freebsd.

Many thanks in advance.

Kent.