The guts of stat cache.

[Christopher R. Hertel]

On 03/20/2013 04:19 AM, Volker Lendecke wrote:
> On Tue, Mar 19, 2013 at 05:22:37PM -0500, Christopher R. Hertel wrote:
>> On 03/19/2013 05:05 PM, Jeremy Allison wrote:
>>> On Tue, Mar 19, 2013 at 04:20:51PM -0500, Christopher R. Hertel wrote:
>>>> Folks,
>>>>
>>>> I'm looking into a corner case problem, and I need to know more about the
>>>> workings of the stat cache.
>>>>
>>>> The problem has to do with small file creates.  Seems that whenever a file
>>>> is created (particularly if the create needs to fail if the file exists), we
>>>> have to do some work going through the possible case permutations of the
>>>> given filename.
>>>>
>>>> Stat cache is supposed to help with that, but I am seeing lots of calls to
>>>> the Samba VFS stat function, asking for info on the same name.
>>>>
>>>> Is the stat cache above or below the VFS layer?
>>>
>>> Above.
>>
>> So it's not replaceable from within a VFS module (augmentable, perhaps, but
>> not replaceable).
>
> If you intercept the SMB_VFS_GET_REAL_FILENAME you will be
> able to do what the stat cache is supposed to cache.

Perfect!

I'll dig there, and see what I find.  Thanks for the tip.

Chris -)-----

-- 
"Implementing CIFS - the Common Internet FileSystem" ISBN: 013047116X
Samba Team -- http://www.samba.org/     -)-----   Christopher R. Hertel
jCIFS Team -- http://jcifs.samba.org/   -)-----   ubiqx development, uninq.
ubiqx Team -- http://www.ubiqx.org/     -)-----   crh at ubiqx.mn.org
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