To allow MariaDBMon to be used with Clustrix we need to handle
Clustrix separately as its apparent version is 5.0.45, which is
lower than what MariaDBMon supports. Further, we must ensure that
Clustrix does not query the slave status as there are no slaves
in the M/S sense in a Clustrix cluster.
NOTE: Once there is a specific Clustrix monitor, this code should
be removed.
Under heavy load some of the basic network operations could fail which led
to some of the allocated memory to leak.
Also the backend protocol never freed the current protocol command if it
was not completed. This would happen if a user executed a session command
as the first command but backend authentication would fail.
The authentication code did not initialize one of the buffers used to
calculate the password hashes. This resulted in the use of uninitialized
memory when the user provided no password.
The test now uses maxctrl to count how many connections there are. This
helps avoid creating new users on the database and works around the slave
syncing problems.
By resetting the replay state the transaction replay can start again on a
new server. This allows the replay process work when a master server is
shutting down.
By delaying the replay for a second, we give the monitor a small chance to
adap to master failures. It'll also prevent rapid re-querying if multiple
transaction replays are supported.
A transaction that just completed will go through the start_trx_replay
function as from the client protocol's point of view the transaction is
still open. The debug assertion did not take this into account and would
fail if a successful commit was the last thing done on master that failed.
Also fixed the formatting.
If a Galera cluster drops down to a single node, the last node would not
be considered valid. During the failure of the second to last node, the
master would also temporarily lose the master status.
The behavior was changed to always keep the cluster UUID until the cluster
size drops down to zero. This guarantees that the same cluster is used as
long as possible.
The TOC was added only to the long documentation files to make them easier
to navigate. Also modified the headings for Avro and Binlog routers and did
some minor cleanup.
When a server is stopping, it'll send an error to the client before
terminating the TCP connection. The code in readwritesplit would detect
this error and create a hangup event on the DCB. This would cause it to
appear as if the TCP connection was broken and the router would
immediately try to reconnect to the same server.
By ignoring the error and allowing the connection to die on its own, we
avoid immediately reconnecting and retrying any transactions on the
stopping server. This increases the chances that the monitor will see it
first and assign the server states correctly before the transaction replay
is attempted.
The assertion would hold true for a single worker but it can't be
guaranteed to be true on a multi-worker system where the statistics are
distributed across the workers.
Enabling the feature by default prevents the master connection from dying
during times when there are very little or no writes. Having a modest ping
interval of 300 seconds serves to minimize the amount of extra work that
both MaxScale and the server have to do while still keeping the
connections in good shape.
Used only with supporting server versions. Using the time limit ensures that
the server interrupts the query at the same point Connector-C would cut the
connection. This prevents lingering queries.
Also, cleans up some associated error messages.
