I have been having poor performance with Samba on my Gentoo-based file server for larger files (videos, 8 megapixel photos, etc). I tried everything, including performance tweaking but couldn’t get Samba to perform for these larger files. When I used scp to move the files across my Gigabit LAN, I’d see 10-20MBps transfer rates, so I knew it wasn’t the NIC driver, file system, or anything else other than Samba.
After reading some similar posts by Ubuntu users from 2006 and early 2007, I decided to upgrade Samba from samba-3.0.24-r3 (the version that was current when I installed Gentoo on this new server about 4-5 months ago) to the latest. Wow, what a difference! Everything is working great now! According to the posts, there have been some performance issues with Samba but they weren’t announced or identified for a little while. The latest stable ebuild for Gentoo seemed to do the trick.
FYI, I’m now on samba-3.0.27a and have the following USE flags: acl cups ipv6 pam python readline swat syslog