Commit 67386980e327ad063b24cb55971cf44f4930e241 caused the actual events
to be ignored. This meant that the larger event size was assumed for all
events. In most cases this works but it is not the correct way to do it.
Up until 2.1.12, if it in the configuration file said
'router_options=slave', the master was used if there were no
slaves at session creation time.
That broke in 2.1.13 as a side-effect of MXS-1516 that checks
at routing time whether the server initially selected as master
still is the master.
Now the required server status is stored separately for each
session, so that if the master was chosen, even though we have
'router_options=slave', we can turn on the SERVER_MASTER bit.
That allows us to handle the case correctly in connection_is_valid().
Single spot where an existing hint ptr was overwritten. Removed gwbuf_add_hint()
because it was adding hints at the opposite end compared to functions in hint.h.
Added hint_splice() to replace.
Defining the [maxscale] section in a configuration file that is not the
root configuration file is now treated as an error instead of silently
ignored.
- If a client DCB should be moved to some other worker than
the current one (cli and maxinfo), and that fails, the
thread id must be reset to that of the calling thread as
otherwise asserts will be triggered.
- If the creation of the first DCB fails, then the dcb list
for that thread will be NULL and thus must be accessed
with some caution.
When the pipe buffer size is maximized, the message queue can hold more
messages. This will mitigate the problem of too many messages being placed
in the queue.
When DCBs are being hung in dcb_hangup_foreach, the hangup event can be
processed directly. This prevents excessive use of the worker message
queue pipe thus reducing the possibility of it being full.
The fact that a client dcb was immediately added to the epoll-
instance of the relevant worker (possible, since that is thread-
safe), but was added to the book-keeping via the message mechanism
(necessary, since that is not thread-safe), meant that if the
connection was closed before the message was delivered, the handling
of the message then caused an access error.
Now the fd is also added to the epoll-instance via the messaging
mechanism, so the problem can no longer occur. The only fds this
affects are connections made to maxadmin or maxinfo as they are
always handled by the main thread due to deadlock issues.
If the feature is enabled (default off), at the end of a monitor loop
(once server states are known), read_only is enabled on slaves servers
without it.
To work around the limitation in the session command handling and
multi-part results, all session commands are now treated as gathered
results. This allows session commands which return result sets to be used
with MaxScale.
This change should not cause problems with practical workloads as they
usually do not return massive resultsets for session commands.
The optimal way to handle the multi-part responses would be to integrate
it into the result completion tracking process. This would allow the
prepared statement IDs to be extracted while the command is being
processed.
Backported the minimal set of changes required to build 2.1 with GCC
8. The format-truncation and format-overflow warnings are disabled instead
of fixed in 2.1 to remove duplication of effort that was already done in
2.2 (the commit doesn't cherry-pick cleanly).
The default database was not extracted correctly as the length of the
user's name did not include the null terminator. Also the comparison for
database name length used the smaller than operator instead of the correct
larger than operator.
When the client reauthenticates via COM_CHANGE_USER the new SHA1 needs to
be stored as the backend connections rely on it being up-to-date.
This commit fixes the regression of the mxs548_short_session_change_user
test.
If the reauthentication of a client that is performing a COM_CHANGE_USER
fails, the users need to be reloaded. Without the reloading, the
reauthentication will fail if new users were added after the last loading
of users.
The parameter extraction caused a recursive lock of the server
spinlock. To work around this, an unlocked version of server_get_parameter
is needed.
Ideally, a lock-free setup would be used but due to this being a bug fix,
it will have to be done later on.
The re-authentication done in MaxScale caused multiple error packets to be
sent for the same COM_CHANGE_USER. In addition to this, the failure of
authentication did not terminate the client connection.
The change in behavior requires the test case to be changed as well.
Multi-statement SELECTs were properly detected and handled,
but e.g. multi-statement UPDATESs were not, with the result
that erronous warnings were logged.
Now the responses are detected and handled properly.
If a connection is killed but the backend DCBs have not yet received their
thread IDs, the connections can be forcibly closed. This removes the
possibility of stale connections caused by an unfortunately timed KILL
query to a session that has partially connected to some servers.
Returning the length of the value instead of a boolean allows the user to
know when the parameter value exceeded the buffer size passed as the
parameter.
To support a wider range of client connectors, MaxScale should respond
with an AuthSwitchRequest packet to all COM_CHANGE_USER commands. Only
MariaDB connectors understand the OK packet as the only response to a
COM_CHANGE_USER but all connectors understand the AuthSwitchRequest
packet.
The mysql_create_standard_error function accepted a packet number as a
parameter but did not use it as the actual packet number. As the value it
used happened to coincide with 50% of the use-cases, it went unnoticed.
The remaining 50% occurred when a KILL command was executed with an
unknown connection ID.
The individual servers were missing a statistic that would give an
estimated query count. As there is no simple way to count queries for all
modules, counting the number of routed protocol packets is a suitable
substitute.
The same problem that caused maxadmin to lock up was also what caused
maxinfo to lock up. The concurrent access to the legacy administrative
functions caused deadlocks.
The resultset processing for MySQL requires some extra work as it lacks
the proper SERVER_MORE_RESULTS_EXIST flag in the last EOF packet. Instead,
the first EOF packet has the SERVER_PS_OUT_PARAMS flag which needs to be
interpreted as a SERVER_MORE_RESULTS_EXIST flag for the second EOF packet.
Also corrected the EOF packet handling to do the flag checks in the code
that deals with the EOF packets.
As the modutil_state parameter is now used for more than large packet
tracking, the correct solution is to store this state object in the
readwritesplit session instead of interpreting it to a boolean value.
