I have a mirrored SQL Server 2012 database. The first server has a hugh tempdb write IO load when the maximum memory limit is set above 8192 mb.
These 8192 where the original setting for both the first and second server and I can only assume this can be an origin of this wierd behavior. However, when I increase the limit on the second server, the first still causes high io load. Once I set it back to 8192 or lower, tempdb activity zeros.
Also changing the mirroring model between High Performance / High Safety / Monitor has no effect. I have not yet tried to remove the mirror as this will cause an application downtime...
Have I found a bug?