This from a friend: -
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Recently we have been seeing some issues with our Business Monitor servers on start up. After running IBM Business Monitor 7.5.1 for over a year, every time we restarted the environment there was a spike in CPU consumption that lasted for over half an hour.
On closer inspection it was the cognos process spawned by Monitor that was consuming all this CPU. A quick call to IBM support pointed us at the NC tables used by cognos. A few of our tables had over half a million rows, where as the following document suggestes anything over 1000 could impact performance:
http://www-01.ibm.com/support/docview.wss?uid=swg21637944
So we followed the steps in the technote and cleared down the NC tables and all of a sudden there was no issue following the next restart.
On closer inspection it was the cognos process spawned by Monitor that was consuming all this CPU. A quick call to IBM support pointed us at the NC tables used by cognos. A few of our tables had over half a million rows, where as the following document suggestes anything over 1000 could impact performance:
http://www-01.ibm.com/support/docview.wss?uid=swg21637944
So we followed the steps in the technote and cleared down the NC tables and all of a sudden there was no issue following the next restart.
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I've checked our own IBM Business Monitor 8.0.1.2 environment, but the NC_ tables are all clear. However, YOUR mileage MAY vary :-)