In case a failure happens when a transaction is failed on PREPARE,
we used to hit an assertion for ensuring there is no pending
activity on the connection. However, that's not true after the
changes in #2031. Thus, we've replaced the assertion with a more
generic function call to consume any pending activity, if exists.
In case a failure happens when a transaction is rollbacked,
we used to hit an assertion for ensuring there is no pending
activity on the connection. However, that's not true after the
changes in #2031. Thus, we've replaced the assertion with a more
generic function call to consume any pending activity, if exists.
It's against our coding convention to call functions inside parameter
lists; when single-stepping with a debugger it's difficult to determine
what the function returned.
That wouldn't be good enough reason to change this code but while
porting Citus to Windows I ran into this line of code.
assign_distributed_transaction_id was called with a weird timestamp and
I wasn't able to find the problem without first making this change.
Postgres provides OS agnosting formatting macros for
formatting 64 bit numbers. Replaced %ld %lu with
INT64_FORMAT and UINT64_FORMAT respectively.
Also found some incorrect usages of formatting
flags and fixed them.
We sent multiple commands to worker when starting a transaction.
Previously we only checked the result of the first command that
is transaction 'BEGIN' which always succeeds. Any failure on
following commands were not checked.
With this commit, we make sure all command results are checked.
If there is any error we report the first error found.
This change adds support for SAVEPOINT, ROLLBACK TO SAVEPOINT, and RELEASE SAVEPOINT.
When transaction connections are not established yet, savepoints are kept in a stack and sent to the worker when the connection is later established. After establishing connections, savepoint commands are sent as they arrive.
This change fixes#1493 .
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.
Previously we used ForgetResults() in StartRemoteTransactionAbort() -
that's problematic because there might still be an ongoing statement,
and this causes us to wait for its completion. That e.g. happens when
a statement running on the coordinator is cancelled.
Hadi Moshayedi
Hadi Moshayedi
Dimitri Fontaine
Murat Tuncer
Onder Kalaci
Marco Slot
Brian Cloutier
Murat Tuncer
Hadi Moshayedi
Marco Slot
Andres Freund