Re: Buddypress Memory Overload
As you said previously; to quote I think the problem is not the memory usage of php, but the usage of the mysql server.
you are probably correct, 10,000 visitors is quite high and you perhaps need to speak to a server tech about optimizing you DB / server for best performance, in the meantime you might perhaps check the WP & BP codex pages for any tips on optimisizing both BP & WP installs and also perhaps start using something like WP Super Cache to minimize DB hits
Other than that I don’t really think this is a BP isssue or at least much you can do from the perspective of the BP install.