mirroring performance on SQL 2005

[Eddiefdz]

Hello All,

Are any of you out there running SQL mirroring? If so, have you noticed any performance issues when using asyncrounous mirroring? According to Microsoft, asyncronous mirriring will commit changes to the primary and then to the mirror, thus speeding up the process instead of syncronous which would have to wait for the transaction to be commited at the mirror before actually recording the tranaction as completed. Well, i have noticed that although I have it set to asyncronous, i notice that the mirror server's disk usage directly affects that on the primary box. For example, i use the mirrored server to run reports by taking a snapshot of the mirrored database. When the mirrored server is really active because of a large report, i see that directly influence the speed of the primary server. Is that normal? I double checked that by pausing mirroring and then once again running a big report off the mirrored box. In that case, the large disk activity on the mirrored box does not influence the primary box at all. Is this normal??

Thanks, and sorry for the long message.

Eddie Fernandez
CCNA, Network+, A+, MCP

 

[JohnBates]

Eddie,

Yes, we use 2005's db mirroring for 2 of our Tier 1 systems.

It was very easy to configure. Has been very reliable and stable as well. (Frankly, I have been surprised)

And when 1 of the servers must be rebooted, the mirror resyncs the data at the failover server.

I do not have a witness server in my configuration - because I don't want the 'automatic failover' to be in effect. Therefore mine is a 2-server mirroring configuration. Client connections have to be redirected so we chose the manual failover option.

Hope this helps. Give it a try!

John