[Samba] degraded performance under domain login load

[Chris Anders]

Hi guys,

Not sure how to diagnose this problem however i have recently  
upgraded one of my schools sites from gentoo to freebsd which moved  
us from samba 3.0.14 to 3.0.21b and the first thing I noticed was  
when the students came to login if they all logged in at once the  
performance of login was crippled to a near standstill!

As a test i swapped in the gentoo box and forced the upgrade to samba  
3.0.21b (incase it was distro related) and to my surprise the same  
problem occurred, a class will come into the computer lab all try to  
login, kixtart will start do its login procedures and everything  
would login at a snail pace, to the point kixtart will lockup and  
generate errors!!!

As the next test, i swaped the fresh installed freebsd system back in  
removed the latest samba from ports and manually installed samba  
3.0.14 and the problem was resolved. This leads me to believe that  
this is not distro specific at all, however a serious problem in high  
load systems of login.

Is there is a way to tune the latest versions of samba to combat this  
problem as i even noticed loading some apps off the network, if  
everyone is trying to access the same app at the same time that it  
too will loads at a snail pace...

I have monitored server load and smbd usage and nothing looks out of  
the ordinary, i have watched logs with nothing standing out as a  
problem...

This computer lab only consists of 25 computers and the server is a  
dual xeon with a 3ware card running raid5 using raptors, so it has  
plenty of IO!
The workstation OS is win2k w/sp4

Any ideas ?



Kind Regards,


Chris Anders
Network Engineer

Anders Networks
Mobile     - 0421 580 017
Email       - chris at anders.net.au
Web         - http://www.anders.net.au

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