On Mon, Jan 18, 2010 at 4:02 PM, Stefan Strasser <strasser@uni-bremen.de> wrote:
the resource only has to make sure that the state that was the basis for signalling a successful prepare-phase in a two-phase-commit is upheld until commit: prepare: returns if the transaction can be committed. commit: publish the local modifications. if prepare signalled a successful transaction, this has to succeed.
Stefan, IIUC, you are essentially proposing we implement resource managers per the XA standard, correct? (http://www.opengroup.org/onlinepubs/009680699/toc.pdf) I'm basing this on your previous reference to BerkeleyDB's XA APIs. How far do you intend to go with ensuring the recoverability of these multi-resource transactions? Specifically, The XA standard requires that RMs persist the state of the transaction during prepare() so that the transaction can still be completed or rolled back, consistently across all RMs even if the two-phase commit is interrupted by process failures. The TM itself must have some form of persistent storage to track the state of all such transactions, for recovery processing. Am I understanding your intention correctly? - Bob