6 Commits (b5ea3ab6a3dc04dd979d3c7393e052ff1a91a854)

Author	SHA1	Message	Date
Onder Kalaci	b5ea3ab6a3	Improve locking semantics for backend management ... We use the backend shared memory lock for preventing new backends to be part of a new distributed transaction or an existing backend to leave a distributed transaction while we're reading the all backends' data. The primary goal is to provide consistent view of the current distributed transactions while doing the deadlock detection.	2017-08-09 17:17:12 +03:00
Marco Slot	81198a1d02	Add function for dumping local wait edges	2017-07-25 16:52:32 +02:00
Onder Kalaci	58faffa42b	Fix bug on error check for assigning distributed transaction id ... to a backend that has already been assigned a transaction.	2017-07-25 14:58:07 +03:00
Marco Slot	601b17d544	Use distributed transaction number in 2PC identifiers	2017-07-21 17:36:33 +02:00
Marco Slot	18a6e478af	Fix typo in GetCurrentDistributedTransctionId	2017-07-21 17:36:33 +02:00
Onder Kalaci	3369f3486f	Introduce distributed transaction ids ... This commit adds distributed transaction id infrastructure in the scope of distributed deadlock detection. In general, the distributed transaction id consists of a tuple in the form of: `(databaseId, initiatorNodeIdentifier, transactionId, timestamp)`. Briefly, we add a shared memory block on each node, which holds some information per backend (i.e., an array `BackendData backends[MaxBackends]`). Later, on each coordinated transaction, Citus sends `SELECT assign_distributed_transaction_id()` right after `BEGIN`. For that backend on the worker, the distributed transaction id is set to the values assigned via the function call. The aim of the above is to correlate the transactions on the coordinator to the transactions on the worker nodes.	2017-07-18 15:01:42 +03:00