recording, within a respective shared data object record for each transaction of the set of transactions, an identification of one or more additional shared data objects on which the corresponding transaction has requested synchronization;

in response to the commit request, examining the shared data object record of the given transaction to identify one or more additional shared data objects on which the given transaction has requested synchronization;

wherein said determining whether to commit or abort the given transaction is based at least in part on a transactional state of an additional transaction identified in a collaborator record of an additional shared data object of the one or more additional shared data objects.