If a fake event is added to the current dcb, we arrange things so
that it is delivered immediately when the handling of the event(s)
during which the fake event was added, has been performed.
Otherwise the event is delivered via the event loop.
The COM_CHANGE_USER that is sent as a part of the reset process for a
persistent connection did not expect a AuthSwitchRequest packet to be sent
as that implies that the server did not take the authentication fast
path. In this case, an error message needs to be logged stating that the
server requested a different authentication plugin than was expected.
The adminusers test did not properly initialize all subsystems in
MaxScale. The polling and DCB tests weren't updated with the changes to
the DCB closing.
dcb_readq_append()
dcb_readq_prepend()
dcb_readq_set()
dcb_readq_has()
dcb_readq_release()
dcb_readq_get()
dcb_readq_length()
No code but for DCB code itself should directly manipulate the
internals of a DCB. Thesse functions will be taken into use in
protocol modules.
Before each event handler is called, it is checked whether the
dcb has been closed. If it has been, then the event handler is
not called.
The check has to be made before each event handler, because any
event handler can close the dcb.
The original process should use _exit if the forking of the child process
is successful. This makes sure that the exit handlers are called only when
the daemon process exits.
The response handling logic did not always take the last packet for
inspection when a COM_CHANGE_USER was executed. The OK packet will always
be the last one since the COM_CHANGE_USER is the last command that was
sent.
Binlog server: force fake Client DCB close in errorReply. This fixes an
issue when START SLAVE, with new config, is called after a previous one
with errors.
The workers need to be destroyed only after services have been
to ensure that they are around in case the destruction of services
involves the closing of dcbs.
If the current worker id is -1, we do not insist that the dcb
is closed by the owning thread. That will happen only for dcbs
that are created before the workers have been started and hence
it is also ok to close them after the workers have exited.
The automatic reconnection feature of the Connector-C was not
enabled. Enabling it should reduce the amount of false positives that the
monitors pick up.
If the session id is known, it will be logged together with all
messages. If present, the session id appears, enclosed in paranthesis,
right after the message category. E.g.
2017-08-30 12:20:49 warning: (4711) [masking] The rule ...
Conceptually this is a cherry-pick of commit
67efd1daeabbc398b8a8fbc0cd02c2af26e4cb6c (2.2), but too much has
changed to actually be able to cherry-pick that commit.
When an unexpected response to a COM_CHANGE_USER is received, it is now
processes and discarded instead of treated as an error. This will allow
further analysis of the situation in addition to possibly solving some of
the problems that the persistent connections have.
Added extra info level logging to relevant parts of the code that deal
with the COM_CHANGE_USER reply processing. This information should allow
tracking of the response state for debugging purposes.
If a dcb being closed is the dcb for which events are currently being
processed, the dcb is not closed immediately but only after all events
have been delivered.
Remove saving/updating GTID repo when maxscale starts.
The repo update slows down the maxscale startup.
The saving was added in order populate GTID repo with current file but
it costs extra time to event validation routine when current binlog has
many events and it has a big size.
MXS-1156: MASTER_CONNECT_RETRY is a new option for CHANGE MASTER TO.
The ‘connect_retry’, ‘master_retry_count’ options are now in use for
both service and
router_options.
If the session id is known, it will be logged together with all
messages. If present, the session id appears, enclosed in paranthesis,
right after the message category. E.g.
2017-08-30 12:20:49 warning: (4711) [masking] The rule ...
This will be used by a subsequent `session_get_current()` and
`session_get_current_id()` for obtaining the current SESSION and
session id, respectively. The latter of those will be used by the
logging mechanism for logging the session id in conjunction with
messages.
The response to the COM_CHANGE_USER should always be turned into a
contiguous buffer of complete packets. This guarantees that the code that
processes it functions properly.
When dcb_close() is called, the DCB is only marked for closing
and the actual closing takes place only after all event handlers
have been called. That way, the state of the DCB will not change
during event processing but only after.
From a handler perspective this should now be just like it was
when the zombie queue was present.
TODO: There are far too many state variables or variables akin to
state variables - dcb_role, state, persistentstart, n_close -
in DCB. A cleanup is warranted.
