Hi again,

I have done some more testing and one thing that took me by surprice at first , was the fact that compressed tables are slower on SSD drives....

Running a ETL job between two REVO Drives (Running the same ETL with everything on one drive is just as fast... )is actually faster if the tables involved are not compressed. I believe that this is because there is no disk latency what so ever and compressing an uncompressing actually adds an extra overhead. CPU's are not fully utilized so that is prabably not the reason either. I have no waits on the server while running the ETL.

When I run the same ETL on normal disks, compressed disks are a bit faster then uncompressed, but there is no dramatic perfromance gain. Space usage on the other hand is wastly reduced.

Any thoughts on this ?

Staffan