Hi,
Current situation :
We recently bought a NetApp FAS 3140 Metrocluster with 26 x 500Gb sata disk for each side. This system is
used to store all our VMware server in NFS volumes. We have a few iSCSI connected LUN's for the Exchange
and SQL Server 2008 (requirement for snapmanagers).
Database info :
- Instance 1 = Database for our WMS system
- Instance 2 = Database for Microsoft Dynamics NAV 5.0
- Instance 3 = Our main database, not yet on this system (soon to be)
Since we migrated our WMS and Dynamics databases to the new SQL Server (on the LUN's) we started having
performance problems when a high load was created on the Microsoft Dynamics system. The WMS and
Dynamics database both slowed down below useable limits.
I have contacted support and got a lot of performance tracking information. At the moment I'm monitoring network,
cpu, disk I/O on the SQL Server and the NetApp system and got lot's of data, but can really firgure out what is
causing the problems so far. So I would be interessed in hearing from anyone who has experience with Micrsoft
Dynamics NAV on NetApp volumes and its performance.
What I have tried so far :
- Tracking latency with perfmon.msc on the NetApp directly (iscsi_read_latency, iscsi_write_latency, iscsi_ops)
- Tracking latency with perfmon.msc on the SQL Server (Avg. Disk sec/Transfer on LogicalDisk)
- Running 'LUN STATS' on the affected LUN
- Running 'SYSSTAT'
The results :
- On the high load moments I can see that the latency on the affected LUN volums is peaking at 300ms and isn't
dropping under 90-100ms. That ofcourse is ways to much above 20ms.
- When trying to generate load on the database by running simple SQL commands outside Dynamics I wrote
around 100.000 records to a new table without seeing the latency go above 2ms.
- Same thing with simple reading of bulk amounts of records.
- When copying files to that volume (2GB file) I can see that the average latency is around 2ms when reading it
and around 300ms when writing it. Don't know why this is like this ?
Questions :
- Is anybody having baseline performance information that I can compare my information to ?
- Is anybody running Dynamics or a high load SQL Server on SATA disks ?
- Are there any performance tuning parameters that I could check/try ?
- I know the peak latencies aren't good/normal, but how can I make sure that it is connected to let's say the
SATA disks and not anything else on the storage or the VMware system ?
Thanks in advance for any extra information on this topic...
