[AFS3-std] File Server/Cache Manager Extended Status Information

[Jeffrey Altman]

This is a cryptographically signed message in MIME format.

--------------ms000208080206090903070906
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

Jeffrey Hutzelman wrote:
> Actually, it may turn out that the improvement you get is the other way around.  The file may change several times while someone else continues to hold the lock.
Of course it might and for each change the client would receive a 
callback stating what range was updated.

The Windows cache manager would make use of this data today by 
invalidating just the affected buffers and then increasing the range of 
data versions for which buffers are valid by one.  This would permit the 
cache manager to minimize the number of reads that must be performed 
from the file server in the future.

This is a natural incremental modification to what the Windows cache 
manager already implements.

Jeffrey Altman

P.S.

The Window CM maintains in the cm_scache_t object both the current data 
version and a minimum valid buffer data version.  The minimum valid 
buffer data version is not incremented as a result of a Store Data, Set 
File Length, Directory modification, etc. that results in a data version 
delta of one.  In that scenario the existing buffer versions held by the 
cache manager are known to be valid and only newly read buffers are 
given the current data version.  This eliminates the need to re-read 
buffers from the file as well as eliminates the need to update the data 
version associated with each buffer as part of the Merge Status operation.

If the delta is not one, the cache manager knows that there was a change 
to the object that was not of local origination and the minimum valid 
buffer data version is set to the new data version value.

In both cases, the Merge Status operation can be performed in constant 
time and without regard to the length of the file or the number of 
cached buffers.



--------------ms000208080206090903070906
Content-Type: application/x-pkcs7-signature; name="smime.p7s"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="smime.p7s"
Content-Description: S/MIME Cryptographic Signature
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--------------ms000208080206090903070906--