samba - Mar 2010 - Performance issues: have eliminated disk and network as cause

Hi,

I'm not entirely happy with the performance I'm seeing using Samba, and
I
wonder if anyone can shine any light.

The server is a Dell PowerEdge 2950 with hardware RAID10, 4GB RAM and a
quad-core Intel Xeon processor.  It's not live yet, so there's no load
from
other tasks.

I've already eliminated the RAID (able to sustain 130-140MB/s for
reads/writes) and the network (GigE, tar | nc to this server and untar'd at
the other end sustains 8-900Mbps) as bottlenecks, which leaves me dealing
with Samba.

Samba is peaking at around 280Mbps (reading and writing a single 500MB file)
and normal performance (which I have benchmarked with a 350MB directory
containing about 1,000 files of various sizes up to 2MB) is closer to
90-100Mbps (write), 117Mbps (read).  This is with a Windows XP client, using
smbmount from a Linux client is not appreciably faster.

Obviously there's going to be a much larger overhead associated with SMB
versus netcat, but 3.5-8 times slower?

I have attached my smb.conf (though I have removed most of the shares for
brevity's sake), in the hope that someone can help.


James.

GOS Networks Limited, 1 Friary, Temple Quay, Bristol, BS1 6EA, UK.

Registered company number: 6917663
 

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Just been told the config file didn't appear in the email as it went out
(even though it certainly appears in the copy I've got), so I'm
attaching
inline this time.

Oh, BTW:  it's version 3.4.7 on Debian Lenny, installed from backports.

[global]
        workgroup = U4EATECH
        netbios name = tiamat
        enable privileges = yes
        server string = Primary Domain Controller %v
        security = user
        local master = no
        os level = 33
        domain master = no
        preferred master = no
        encrypt passwords = true
        null passwords = no
        hide unreadable = yes
        hide dot files = yes
        obey pam restrictions = Yes
        unix password sync = Yes
        remote browse sync = 172.30.20.109 172.30.20.130 172.27.0.6
        enhanced browsing = yes
        passwd program = /usr/sbin/smbldap-passwd %u
 passwd chat = "Changing UNIX and samba passwords for*\nNew password*"
%n\n
"*Retype new password*" %n\n"
        ldap passwd sync = Yes
        log level = 0
        syslog = 1
        log file = /var/log/samba/log.%m
        max log size = 1000
        read raw = yes
        write raw = yes
        kernel oplocks = yes
        max xmit = 65535
        dead time = 15
        use sendfile = yes
        socket options =  TCP_NODELAY SO_KEEPALIVE IPTOS_LOWDELAY
        getwd cache = yes
        mangling method = hash2
        Dos charset = 850
        Unix charset = ISO8859-1

        logon script = logon.bat
        logon path         logon home = \\atlas\%U
        logon drive = H:
        domain logons = Yes
        wins server = 172.30.20.109
        #name resolve order = hosts bcast
        name resolve order = wins lmhosts hosts bcast
        dns proxy = yes
        time server = yes
        passdb backend = ldapsam:"ldap://ldap.u4eatech.com/ ldap://
ldap-slave.u4eatech.com"
        ldap admin dn = cn=smbadmin,dc=u4eatech,dc=com
        ldap suffix = dc=u4eatech,dc=com
        ldap group suffix = ou=Group
        ldap user suffix = ou=People
        ldap machine suffix = ou=Hosts
        ldap idmap suffix = ou=People
        ldap ssl = no
        add user script = /usr/sbin/smbldap-useradd -m "%u"
        ldap delete dn = Yes
        delete user script = /usr/sbin/smbldap-userdel "%u"
        add machine script = /usr/sbin/smbldap-useradd -w "%u"
        add group script = /usr/sbin/smbldap-groupadd -p "%g"
        delete group script = /usr/sbin/smbldap-groupdel "%g"
        add user to group script = /usr/sbin/smbldap-groupmod -m "%u"
"%g"
        delete user from group script = /usr/sbin/smbldap-groupmod -x
"%u"
"%g"
        set primary group script = /usr/sbin/smbldap-usermod -g "%g"
"%u"
        load printers = no
        create mask = 0640
        directory mask = 0750
        nt acl support = Yes
        guest account = nobody
        dont descend = /proc,/dev,/etc,/lib,/lost+found,/initrd
        #show add printer wizard = yes
        ; to maintain capital letters in shortcuts in any of the profile
folders:
        preserve case = yes
        short preserve case = yes
        case sensitive = no

[netlogon]

        path = /home/samba/netlogon
        guest ok = yes
        browseable = No
        read only = no

[wpkg]
        path = /home/samba/wpkg
        read only = yes
        guest ok = yes
        browseable = no
[homes]
    comment = Home Directories
    browseable = yes
    writable = yes
    oplocks = yes

GOS Networks Limited, 1 Friary, Temple Quay, Bristol, BS1 6EA, UK.

Registered company number: 6917663
 

The information in this email is confidential and may be legally privileged.
It is intended solely for the addressee. Access to this email by anyone else
is unauthorised. If you are not the intended recipient, any disclosure,
copying, distribution or any action taken or omitted to be taken in reliance
on it, is prohibited and may be unlawful. When addressed to our clients any
opinions or advice contained in this email are subject to the terms and
conditions expressed in the governing GOS Networks agreement.