[Samba] No increased throughput with SMB Multichannel and two NICs

[Daniel Vogelbacher]

On 06.09.2016 20:15, Jeremy Allison via samba wrote:
> On Tue, Sep 06, 2016 at 08:06:48PM +0200, Volker Lendecke via samba wrote:
>> On Tue, Sep 06, 2016 at 07:58:27PM +0200, Daniel Vogelbacher via samba wrote:
>>> I don't have these options in my smb.conf.
>>> Do you recommend any specific values?
>>
>> aio read size = 1
>> aio write size = 1
>>
>> You might try with current master. There we have improved async I/O
>> handling significantly.
> 
> Yep. Without those values smbd reads/writes synchronously, meaning
> issuing two requests down different TCP sockets still get serialized
> in the server. With aio turned on they'll get handed to a pthread
> pool to complete, allowing as many requests as your client will send
> to be outstanding (and your disk and network bandwith will allow of
> course :-).
> 

Oh great, now it works much better!

I've added:

vfs objects = aio_pthread # very important!!!
aio read size = 1
aio write size = 1
read raw = Yes
write raw = Yes
strict locking = No
socket options = TCP_NODELAY IPTOS_LOWDELAY SO_RCVBUF=131072
SO_SNDBUF=131072
min receivefile size = 16384
use sendfile = Yes

Transferring a file from share(linux,tmpfs) to Windows SSD hits >2GBit/s
now.

But transferring from Windows SSD to linux-tmpfs share still only hits 1
GBit/s (~500MBit per interface).

The SSD is fast enough to deliver 2GBit/s and on samba-side no disks
involved (tmpfs).

Is there maybe another option required?


Regards
Daniel Vogelbacher