Looking for a new way to speed up your MySQL server? The tcmalloc library from Google Perftools could be the answer (about 15-20% performance improvement). Refer to this (updated) How-to for more information.
I just packaged Google Perftools 1.4 for Debian 5.0 (a.k.a. “Lenny”). According to the Changelog, they’re bringing a lot of bugfixes and improvements, and then they enhance the stability of the daemons they’re plugged in, especially on 64bits systems.
Upgrading from previous version is highly recommended.