We've
typically seen performance increases when moving from local storage to the
filer.
What
kind of pipe are you using? If you're using 100 Mbps Ethernet, you'll see
a performance hit since that's at best 8 MB/sec network throughput, which is
trivial compared to local attach. If you are using gigabit Ethernet you
should see excellent performance.
Also
how many disks are you using? Just like with local storage, more spindles
= better performance.
Are
you using a private (or at least dedicated) network connection for the SQL
Server to filer connection? If you're sending SQL queries to the box on
the same interface that is talking to the filer that could cause significant
performance degradation.
Finally are you using OLTP or OLAP databases with the filer? (i.e. random
or sequential reads?) NetApp folks might disagree but I think WAFL is a
bad thing to mix with OLAP if you're using snapshots. It's great,
absolutely phenomenal for OLTP, but sequential reads are not a filer's
strong point (that's why it's called write ANYWHERE file layout, not "Write In
Order and Minimize Fragmentation File Layout").
(Please no flames on how WAFL minimizes fragmentation--if you're
using snapshots and you change any data in a database, the new data will be
written elsewhere than the original disk location, causing the head to jump
around like mad during what should be sequential reads. A copy-on-write
snapshot would be MUCH better in this scenario.)
Tell
us more about your configuration so we can try to figure out why you're seeing
problems. Also try pinging your sales rep, NetApp has people dedicated to
making SQL Server work well with filers and I'm sure you could get some pointers
from them.
MD
Has anyone placed a SQL database on a filer and
seen a significant performance increase of 10% or more or a
performance decrease of 10% or more?
Our initial test of a source change management application using a SQL
database on our filer showed a significant decrease in performance to the tune
of 2-3 times slower than a local storage array. We understand ours
wasn't an apples to apples comparison but we weren't expecting the difference
to be this great.
Has anyone else experienced a similar story where they have seen
negative/positive results they would like to share?
Our filer is a model F840.