[Gluster-devel] AFR documentation

[Chris Johnson]

On Fri, 19 Oct 2007, Thierry EXCOFFIER wrote:

      My $0.02.  First rule of both science and engineering, never
assume.  It almost always causes big problems.

> Krishna Srinivas wrote:
>>>    - If the version numbers are identicals, do you detect that
>>>      the file content is not the same ?
>> 
>> No. But we can have improve the safety level to handle such cases
>> by further checking if the copies differ by mtime (by more than 30 secs, 
>> say)
>> or if they have different file sizes etc in which case we can return EIO.
>> Again suggestions are welcome.
>
> Can you store the IP of the last client who have modified the file ?
> If the version is the same but not the client IP then the file
> content is in an inpredictable state.
>
> May be you could assume that if the file is wrote by more than one
> client then the *user application* has locked the file before.
> In this case you need an option to indicate to AFR that
> the file locking succeed only if all the clients are up.
>
> Hope my 2 cents may help.
>
> Thierry.
> -- 
> Thierry.EXCOFFIER@@liris.univ-lyon1.fr//   GO: Oriental Strategy Game
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>
>
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>
>

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