AIO, SMB2 and Samba 3.6

[Volker Lendecke]

On Tue, Feb 21, 2012 at 05:42:28PM +1100, Andrew Bartlett wrote:
> On Mon, 2012-02-20 at 10:35 +0100, Christian Ambach wrote:
> > Hi Andrew,
> > 
> > On 02/20/2012 03:14 AM, Andrew Bartlett wrote:
> > > I have this report that AIO and SMB2 don't work in Samba 3.6.3.  (Win2k8
> > > creates empty files).
> > 
> > Would be nice to know with which aio settings and which aio module this 
> > happens.
> 
> With:
>  aio read size = 1
>  aio write size = 1
> 
> As far as I can tell, this is with the default AIO backend on Linux
> (there are no additional AIO patches, just --with-aio-support). 
> 
> I have network captures (the success case is too large to post to the
> list), but essentially the SMB2 write request is never answered, and
> eventually (1 min after the last send write) the connection is dropped. 
> 
> The transfer was from a Samba4 server to a Samba 3.6.3 NAS, via a
> Windows 2008R2 VM. 
> 
> This all works when AIO is disabled on Samba 3.6.3.
> 
> Naturally, I'll keep digging into this, but any clues you can provide
> would be most appreciated. 

A debug level 10 log of smbd and the network captures might
give a hint about what is going on.

With best regards,

Volker Lendecke

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