The `global` parameter causes the time window defined by the `time`
parameter to be applied at the instance level instead of the session
level. This means that a write from one connection will cause all other
connections to use the master for a certain period of time.
Using a configurable time window for consistency is not good as it is not
absolute and cannot adjust to how servers behave.
One example that demonstrates this is when a slave is normally lagging
behind by less than a second but some event causes the lag to spike up to
several seconds. In this case the configured time window would no longer
guarantee consistency.
Another reason to avoid a "static" time window is the fact taht it
prevents load balancing in the cases where slaves catch up to the master
within time window. This happens when time is configured to a higher value
to avoid inconsistencies at all costs.
Added a test case that verified the feature works.
The number of sessions wasn't always incremented but it was always
decremented. This happened primarily when authentication failed. By making
the management of the counters a part of the object lifecycle, this
problem goes away.
The number of sessions wasn't always incremented but it was always
decremented. This happened primarily when authentication failed. By making
the management of the counters a part of the object lifecycle, this
problem goes away.
The client count was incremented before authentication was complete, and
should be decremented if it fails. Otherwise service connection limit can
be easily reached.
RENAME TABLE is now fully supported and works as expected. With the fix to
table versioning, the new table name will receive the latest version
number.
The table versions are now stored in memory and are only resolved on
startup. This simplifies things and removes the need to know where the
data is stored as that information is not available to the Rpl class.
This adds preliminary support for renaming tables. There is still a
problem where the table version will always be set to 1 on a rename. This
should not be done and the version should be set to the largest value that
ever was for that table.
When lazy_connect is enabled and the first query is `SET autocommit=0`, a
master connection can be created. If it is, then the m_current_master
pointer must also be updated.
Also fixed the case where a failure to connect to one slave would cause
the connection attempts to stop too early.
TIMESTAMP2, DATETIME2 and TIME2 values with decimal parts are now
correctly converted into their string forms. Previously the decimal part
was ignored but most of the code required to extract it was in place.
The unsigned integers that would previously be interpreted as negative
values are now correctly converted into their corresponding avro
values. Due to a limitation in the Avro file format, 64-bit unsigned
integers cannot be represented in their unsigned form.
Since both the signed and unsigned versions of a 32-bit integer cannot fit
into a single Avro int, the type for these was changed to long. This is a
backwards incompatible change which means files generated with older
versions will not convert unsigned values correctly.
The unsignedness of a column is now retained in the Column type as well as
the JSON schema. This allows correct conversion of unsigned integer types
which will be done in a later commit.
This allows the same verbose information to be logged in the cases where
it is of use. Mostly this information can be used to figure out why a
certain session was closed.
By doing the reconnection only when a new query arrives, we prevent the
excessive reconnecting that is done when a server's actual and monitored
states are in conflict.
Galeramon will now only use the larger cluster in case a split brain
situation occurs. If the clusters are of equal size, the one whose UUID
compares less will be used. This will guarantee that all MaxScales that
see the same picture will end up using the same cluster.
Because of how the user-data was read, the same service name could be
found multiple times if the user-search query matched multiple rows. Now
the service names are read to a set, which ignores duplicates. The same
service may be attempted again if the authentication fails and user-data
is fetched again.
Authenticators and monitors now use SSL when configured. The fix has two parts:
1) Removed the extra SSLConfig inside SSLProvider, as SSLContext already contains
the config.
2) When inputting parameter values to mysql_ssl_set(), empty strings are converted
to NULL-pointers as the function expects those for unused values.
name_lookup() now returns all results given by getnameinfo(). When searching
for a server, finding one matching address in the lookup-results is enough for
a match.
Also, added a test for name_lookup(). The test is minimal on its own, as hardcoded
test cases are not generally valid.
The new server pam plugin does not always send the first password prompt with the
AuthSwitchRequest-packet. In this case the server expects the client (MaxScale) to
just send the password immediately. MaxScale now checks the length of the packet,
sending the password if the packet is short. This works with both old and new server
versions.
If a master failed during an ongoing session command history replay, it
would be treated as if a normal session command failed which would result
in the already executed session command being re-executed on all servers
at the wrong logical position.
To fix this, the history replay must be distinguished from normal session
command execution. When a connection replaying the history fails, the
query routing simply needs to be attempted again.
If session command execution during server reconnection caused a query to
be queued, the query would be put on the tail end of the queue. This would
cause queries to be reordered if the queue wasn't empty. The correct thing
to do would be to put the next pending query back at the front of the
queue.
If a master reconnection occurred after the session command history was
disabled due to the limit being exceeded, a debug assertion would be hit
in prepare_target. This assert makes sure that a connection can be safely
created to the server which means that in release mode builds the session
state would be inconsistent on the new master.
As this is an unrecoverable situation, the session should stop immediately
even if delayed_retry is enabled. Currently the session will continue
until the delayed retry timeout is hit. This happens due to the fact that
the delayed retry mechanism handles all errors in a similar way.
