Volume snapmirror shouldn't have that classic problem. Volume snapmirror is block based, and therefor doesn't care about the number of files. Qtree snapmirror interacts with WAFL the same way any file level application might, so qtree snapmirror might be the wrong choice, if that's what they are using.

I'd like to know more about their setup, and their snapmirror relationship.

-Blake

On 12/29/06, Julio Calderon jcalderon@agami.com wrote:

Everyone has a challenge with high numbers of small files and to add to that challenge; you are using one of the slowest ntap gear out in the market.

-----Original Message----- From: Thomas Bleek [mailto:bl@gfz-potsdam.de] Sent: Fri Dec 29 09:46:45 2006 To: Toaster Admins Subject: Snapmirror transferrates??

Hello,

I wonder what transferrate I could expect for snapmirror volumes (an/or qtrees) between 2 FAS270 directly connected with Gigabit Ethernet.

We use one filer as NFS backing store for our Mailsystem (Communigate Pro) with mdir mailbox format, so we have many small files here.

I see abnormal high lags with really moderate sizes of the transferred data.

For instance we need about 20 to 40 minutes to transfer 100 to 600 MBytes!

The filesystems a 50% filled 250 GByte Volume/qtree with 10.3 million files (with 7 mio free inodes).

so the average filesize is about 12KByte.

We use Ontap 7.0.4 here and will upgrade to 7.0.5 next week. But I don't really have much hope that this will change the problem.

Could anybody give me some data about his/her transfer rates? I really can't believe, that this slow transfers are normal.

An repeatedly snapmirror status command on the filer shows this:

at first the transfer startet and transferred about 68 MByte in 80 seconds. after that it paused for 15 minutes (output constantly "transferring 68MB done"). from minute 16 to 26 it says "transferring inodes". in these 11 minutes it transferred 225.000 inodes. after that it transfers data again. in minute 28 it has transferred 550 MBytes. after that one minute pause and then the status is idle.

Has netapp/snapmirror a big problem with small files? I don't want to switch to mailbox format because I like the advantages of mdir (single copy mailstore, easier backup?)

Thanks for any hints, thomas