Upgraded from MR2 to MR3 a few weeks back and have a lot of reports where performance is dire since the upgrade.
They are quite complicated reports on top of a 700mb cube but in MR2 they took 1-2 minutes maximum running time, to produce a 50page PDF of size 1.5mb. Using MR3 it takes forever.
The reports open in PPClient connected to the remote cube in seconds, although I will say that paging to the bottom of the report takes a while, as does saving as 'PDF'.
Server is Windows 2003, dual processor with 8gb of RAM.
Any ideas or performance advice?