[ZODB-Dev] More ZODB POSKeyErrors with 2.6.0

[Chris Withers]

Jeremy Hylton wrote:
> It would be interesting to save a snapshot of the index and the
> storage itself.

There are 3 FileStorages storages involved, totalling about 600Mb :-(

>  It seems like there are three serious possibilities:
> 
>  - A corrupted index file gets loaded; the index doesn't match the
>    data in the file.
> 
>  - There is no index, but there is a bug in the code that creates an
>    index from the storage.
> 
>  - There's a bug in the fsIndex code that causes the index to become
>    corrupted at runtime.
> 
> I'd observe that since you continue to see these errors after
> upgrading to the latest BTrees code, I find it less likely that any of
> the errors were the result of BTrees bugs.

And it also seems to be the case that the bug occurs very infrequently, but when 
it does, it futzes something such that it stays futzed until the indexes are 
deleted and the storage server restarted.

cheers,

Chris