Hi
We have setup database mirroring in SQL Server 2014 Standard edition with high safety mode on. Both servers are using identical hardware and have been setup exactly the same. Maximum disk throughput is around 250 MB/s on both servers, and we can transfer data between the servers at 250 MB/s. For most tasks the database mirroring works fine, however, when we run the maintenance tasks to reorganize the indexes it takes at least 5 times as long as it does with mirroring turned off.
The send rate and new transaction rate in the database mirroring monitor is only around 20 MB/s.
The network IO during the index rebuilds is around 60 MB/s, and the disk activity is around 80 MB/s.
The database we are testing against is about 200GB with about 20 fragmented indexes.
The logs are backed up every 5 minutes during index maintenance.
We expected the index reorganizing to take longer with mirroring switched on, but not over 5 times as long. Has anyone else experienced these performance issues with index reorgs / rebuilds on a mirrored server? If so, are there any solutions to make it rebuild faster?
Thanks
