[OpenAFS] Re: experience of SQLite on AFS

Simon Wilkinson sxw@inf.ed.ac.uk
Mon, 26 Apr 2010 06:59:49 +0100


On 26 Apr 2010, at 04:18, Brandon S. Allbery KF8NH wrote:
>>=20
>> If I understand Simon correctly, clients are also not getting file
>> updates while the file is opened O_RDWR. That would still seem to be =
a
>> problem even if we flush on unlock.
>=20
> Flushing will update the server, which will break callbacks as =
necessary.

No, this is still a problem. If a client believes that it has dirty =
chunks, then it ignores callback breaks in favour of preserving the data =
already in the cache. It would appear that, on Linux at least, simply =
opening a file O_RDWR is enough to cause the cache manager to mark the =
file as being dirty. In this situation, you'll never see updated data =
from the server. Both this problem, and the lack of flushing, need to be =
fixed.

Cheers,

Simon.