[Samba] 1 byte writes

[Jeremy Allison]

On Wed, Mar 08, 2006 at 08:17:14PM +0100, Thomas Limoncelli wrote:
> Jeremy,
> 
> Thanks for your continued support.
> 
> >Hmmm. Not sure. What application is doing this ?
> 
> As it's hard to get structured valid information from [our] users, I can 
> only guess it's a particular CAD application. (They're claiming that 
> "everything" runs slowly, but that's yet to be seen once this particular 
> issue is solved.)
> 
> >Your settings seem
> >fine - the client should be using the allocation roundup size to
> >extend, so should only by writing one byte per 1 meg, but it seems
> >to be doing much smaller offsets than that. Try playing with the
> >allocation roundup size parameter - make it larger and see what
> >effect it has on the app. 
> 
> How/when exactly is the allocation roundup size passed to the client 
> over the wire? I'd like to double-check with Ethereal that clients 
> receive the desired value.

It's in the trans2 qfileinfo calls. Look at the SMB_INFO_STANDARD,
SMB_FILE_STANDARD_INFORMATION, SMB_QUERY_FILE_ALLOCATION_INFO
SMB_QUERY_FILE_ALL_INFO calls. 

The function that generates this is get_allocation_size() in
smbd/trans2.c.

> XFS, kernel 2.6.11.4-21.11-smp from the latest SuSE 9.3 updates.

That should be fine.

Jeremy.