[Samba] Samba + LDAP + IIS = massive memory usage

[Martin Edwards]

Dear readers,

I'm not sure if this is a bug or a problem we are causing which is why I'm
posting to the list first in the hope that someone else might have come
across it.

We have been using Samba quite successfully for a number of years.  However,
with this new setup we have a problem.

We're using Samba as a backend for a web farm - 6 or 7 Windows servers
running IIS with all the website data under UNC paths and all the anonymous
web users and app pools running as domain users.

Samba itself uses an LDAP backend.

This setup works very nicely for our needs however we have an issue in that
each Samba process belonging to one of the web servers seems to consume RAM
indefinitely until it is killed.  When the servers are busy each thread can
use 1GB in 20 minutes.

Obviously this is extremely abnormal memory usage.

My only guess is that, when a page is requested on a website and not found,
Samba allocates the memory and does not free it?

We have tried Samba 3.0, 3.2 and 3.3 (various iterations) and have
experienced exactly the same problem.

Can anyone offer any insight.  I would be most grateful.

Martin.

[global]
        csc policy = disable
        deadtime = 25
        dead time = 25
        admin users = root
        max mux = 5000000
        max open files = 5000000
        workgroup = PWMDERBY
        netbios name = GAR
        enable privileges = yes
        smb ports = 139 445
        server string = Samba Server %v
        security = user
        encrypt passwords = Yes
        obey pam restrictions = No
        ldap passwd sync = Yes
        ldap timeout = 5
        log level = 0
        syslog = 0
        log file = /var/log/samba/log.%m
        max log size = 5000000
        time server = Yes
        socket options = TCP_NODELAY SO_KEEPALIVE SO_RCVBUF=8192
SO_SNDBUF=8192
        mangling method = hash2
        Dos charset = 850
        Unix charset = ISO8859-1

        domain logons = Yes
        os level = 255
        preferred master = Yes
        domain master = Yes
        wins support = Yes
        passdb backend = ldapsam:"ldap://192.168.1.4"