samba - Aug 2009 - Tuning the performance of Samba over LAN network to improve I/O performance

Hello friends,

I am trying to test NAS I/O performance over a network and trying to see the
numbers for write and read speed. I have successfully configured and ran a
lot of tests. However the numbers have not increased, I have reached a
bottleneck.

I tried playing around with the smb.conf file including all possible
variations like,

socket options = TCP_NODELAY SO_RCVBUF=(tried values like 8192, 65535,
131070) SO_SNDBUF=(tried 8192, 65535, 131070)
log level = 0 or 1
max xmit = used different numbers ( like 8192 to 65535)

I also tried using
read raw = yes
write raw = yes
but the numbers or the write and read performance does not improve.

My setup is as follows:
I have a Linux machine running ubuntu which is the host and I have it
connected to a Windows XP machine over the network and there is also an
E-SATA which I mount and try to test on. There is Iozone3 and samba server
running on linux.
I also have samba on the network.

The approximate average numbers I am getting over LAN are:

Write: around 23Mbits/sec
Read: around 33Mbits/sec

Please let me know of cases I can try and shoot up the performance.

Any help is appreciated.

Thanks.

> The approximate average numbers I am getting over LAN are:
>
> Write: around 23Mbits/sec
> Read: around 33Mbits/sec
>
>   
Do you really mean Megabits? Or MegaBytes? 33 Megabits (about 4 MB/sec) 
would be VERY abnormal!

Do you have "use sendfile = yes" in your smb.conf? It can be a global 
option or a per-share option.

On Wed, Aug 05, 2009 at 06:42:07PM -0500, Himanshu Thapar
wrote:
> 
> I tried playing around with the smb.conf file including all possible
> variations like,
> 
> socket options = TCP_NODELAY SO_RCVBUF=(tried values like 8192, 65535,
> 131070) SO_SNDBUF=(tried 8192, 65535, 131070)
Remove these. You won't second guess the kernel.
> log level = 0 or 1
> max xmit = used different numbers ( like 8192 to 65535)
Also, don't touch the above, expecially max xmit.
> I also tried using
> read raw = yes
> write raw = yes
Not used on an XP client.
> My setup is as follows:
> I have a Linux machine running ubuntu which is the host and I have it
> connected to a Windows XP machine over the network and there is also an
> E-SATA which I mount and try to test on. There is Iozone3 and samba server
> running on linux.
> I also have samba on the network.
> 
> The approximate average numbers I am getting over LAN are:
> 
> Write: around 23Mbits/sec
> Read: around 33Mbits/sec
Seems low, what filesystem/network card are you using ?

Jeremy.

On Wed, Aug 05, 2009 at 07:11:54PM -0500, Himanshu Thapar
wrote:
> For the numbers I am getting....Writing averages around 23Mbytes/sec and
> Reading averages around 33Mbytes/sec. I am aiming for 30 plus for writing
> and around 40 for reading. Both seem to be reasonable.
True, but first use hdparm to see what your
raw disk numbers should be. Also you first
posted Mbits/sec, not Mbytes, which were *very* low
numbers :-).

Jeremy.

On Wed, Aug 05, 2009 at 07:34:51PM -0500, Himanshu Thapar
wrote:
> Thank you....Okay......can you explain how can I go about with hdparm or
> guide me to an appropriate link. Also how will this help me in diagnosing
> the current problem?
Sorry, you need to learn to use hdparm before you
can do any performance diagnostics. Google for the
command, and read up on it.

Jeremy.

> How can I go about configuring my LAN hardware to use Jumbo Frames?
>
That would be a too long conversation and now I don't have the necessary 
energy.
You can Google for Linux Jumbo Frames. You must identify your LAN card 
and see its specifications. Also, you need to be sure that your switches 
support Jumbo Frames.

I am on a Red Hat system and in my case the file 
"/etc/sysconfig/networking/devices/ifcfg-eth#" contains the following
line:

MTU=9014

This is for a Intel Gigabit LAN card.

I don't know it resides in the same place with Ubuntu.

Look for the ifconfig command and study its parameters.


As for hdparm:
You can see your hard disks transfer rates by executing the following:

hdparm -t /dev/hd(x) where x is the letter of your particular drive.

This is for ATA drive. In the case of SATA or SCSI, it would be /dev/sd(x).

This will give you the throughput of your drive *inside* your system. 
You can now try to make your LAN transfers get as close to that as possible.

As an example, in one of my systems the command "hdparm -t /dev/sda" 
gives me the following output:

/dev/sda:
 Timing buffered disk reads:  350 MB in  3.01 seconds = 116.18 MB/sec

I am not in a position now to give you the LAN throughput of this system.

I hope that this helps somewhat.

On Wed, Aug 05, 2009 at 05:46:19PM -0700, Jeremy Allison
wrote:
> On Wed, Aug 05, 2009 at 07:34:51PM -0500, Himanshu Thapar wrote:
> > Thank you....Okay......can you explain how can I go about with hdparm
or
> > guide me to an appropriate link. Also how will this help me in
diagnosing
> > the current problem?
 
The following thread on Ubuntu Forums is an excellent guide to hdparm:

http://ubuntuforums.org/archive/index.php/t-16360.html

Also, read the man page.

Hallo, Himanshu,

Du meintest am 05.08.09:
> The approximate average numbers I am getting over LAN are:
> Write: around 23Mbits/sec
> Read: around 33Mbits/sec
Try "netio" for checking the possible transfer rate:

   http://arktur.de/Wiki/Zusatzprogramme:netio

Viele Gruesse!
Helmut

I'm in the process of migrating from a Samba PDC to a Win2k3 PDC (all member
servers will remain as Samba boxes).

NEWDOMAIN = new Win2k3 PDC 
OLDDOMAIN = current samba PDC
OLDDOMAIN_MEMBER = a current samba box that's a member of OLDDOMAIN

I've successfully established a trust relationship between OLDOMAIN and
NEWDOMAIN where OLDDOMAIN trusts NEWDOMAIN. Users in NEWDOMAIN have full access
to resources on the OLDDOMAIN PDC.

Where I'm stuck is granting access to OLDDOMAIN_MEMBER to users in
NEWDOMAIN. OLDDOMAIN_MEMBER is joined to OLDDOMAIN and works as expected (Users
in OLDDOMAIN can access resources on OLDDOMAIN_MEMBER. But users in NEWDOMAIN do
not.

Can someone help with the general concept here? Should it work as I've
configured it? Does OLDDOMAIN_MEMBER need to be running winbind against
OLDDOMAIN PDC, or even NEWDOMAIN? (although I don't see how the latter would
work without moving OLDDOMAIN_MEMBER to NEWDOMAIN).

Sorry if this is confusing -- tried to make it as clear as possible.

Steve