Hi There,
We found the solution. It seems that after the installation of fixpack 4 of Cognos
Is the answer. the report run now 40 seconds.
In the bugfix list there is no mention of this problem but it works for us. 
I’ve been looking for the last week for an answer. I installed Cognos 8.4.1 on a Windows 2008 R2 64 bits Server (I have too, because its a standard and therefore mandatory). I installed the latest service pack (on Windows and Cognos).
I’ll use for the content store a SQL 2008 server and for the databases Sybase 12.5 and Sybase 15.5.
So I thought I had to install the Client Drivers on the dispatchers (I’ve got 2 brand new very Fast HP (16 cores)). So I installed the Sybase Client driver 15.5. First I did the 64 bits drivers.
The performance of a couple of reports went from 1 minute to 12 minutes. The CPU went to 100%. So I thought maybe because the Bibus and the report services are still 32 bits, I had to install the 32 bits version. No change at all. The same outcome.
So I installed the sybase client drivers 12.5 (32 bits) and my reports run again very quickly (less then 1 minute). And hardly any CPU usage.
So next I thought that the ini file COGDMCT.ini had to change. But a lot of the parameters don’t tell me a thing.
In COGDMCT.ini I set joined=T and direved=T. So the server can join and make use of derived tables. Also the rows I set to 5000.
These setting I had use with all the versions of the drivers.
?? Is there anyone with the same experience or maybe someone with an answer or tips ??
With regards,
Nico Raspoort
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