Hi Peter, we use dotLRN for www.aiesec.net with 100k users in roughly 3000 communities (same behaviour as a class if I'm not utterly mistaken). And it runs reasonably well. We are at the moment finding the culprits and will provide some tuning suggestions once we are done with it. As for the sitemap, no, not a big issue. It takes 40 seconds to load all the entries into the cache, but this only happens during the startup, so it is fine.
To be fair, let me state the hardware:
- 2*933Ghz, 1GB RAM server with a seperate RAID system for the content-repository-files for the aolserver
- 2*Opteron242, 4GB RAM with multi channel RAID SCSI 15K for the Oracle database.
