DB2 tuning for WCM JCR v6 DB

We are still in the WPS/WCM migration study process (from v5.1.0.4 to v6.0.1.3) and we experience a lots of problems due to the WCM data migration. We have a quite large WCM database (approx 10 Go), and as for today we have 2 big problems with the migration:

- WCM data migration takes 13 days to complete !
- After the import on the target v6 is completed, the portal serveris very slow (very bad response time caused by WCM).

We are currently re-starting the migration from scratch because these performances issues might be due to a problem in the DB2 collation configuration (see). The information provided in the infocenter is simply not correct and can lead to bad performances problems when installing the WCM JCR database....

I will do a specific and detail blog post to share our problem with everyone later on, but while searching for DB2 performances issues, I found these 2 articles which are very useful:

The first one is a very good synthesis of the main tuning tips and tricks (on WPS, WCM, LDAP, http server) that has been published so far on the subject (this is the better synthesis I have found so far, and it is very useful because there are so much distinct tuning guide on these topics and it is really hard to have a good overview of all required tuning actions):

Checklist for optimum performance of WCM 6.0 and 6.1

The second one is especially dedicated to WCM JCR database tuning for DB2 (there are a lot of tuning task that are presented here that I never seen before, but the author seems to be very knowledgeable):

IBM WebSphere Portal Web Content Manager and DB2 Tuning Guide.pdf (DeveloperWorks)