On Thu, Nov 12, 2009 at 1:34 AM, Christian Theune <c...@gocept.com> wrote: > Hi, > > in ZEORaid we're using the storage (a ZEORaid instance) as it's being by > ZEO for recovering data from the good storages into one we're recovering. > > For finishing the recovery exactly on transaction boundaries and to > avoid transactions slipping in when we think we're done we acquire the > commit lock for a short period of time. > > If a client tries to write in that period of time the transaction will > be put into the StorageServer's waiting list and sit there either > indefinitely or until another client comes around calling abort() or > finish(). > > So this is basically an issue because StorageServer assumes that it or > another instance of StorageServer is ever talking to that storage, so it > implements a secret protocol (the waiting list) which is not officially > visible to other code. > > I can hack around this for now by making the waiting list visible to my > code and notify the waiting storages from there, but, I'd like to > propose an extension to the storage API. > > We basically need the ability to register callbacks with a storage that > will be called on transaction boundaries. With that we can redo the > current _restart implementation so that it can be triggered from code > that doesn't need to know that a storage is being wrapped in such a way. > > If you think we can go down that route in general, then I'll prepare a > more detailed proposal including making a draft implementation.
I don't understand what you are trying to say above. Perhaps a more detailed proposal will make it clearer. BTW, I've refactored the waiting list code quite a bit on the jim-thready-zeo2 branch, which I plan to merge to trunk soon. Jim -- Jim Fulton _______________________________________________ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
