If all but one server in a cluster fail and `failover` is enabled for
mysqlmon, the last server would be used as if it were a master. With this
change, the restrictions on failover also require that the last server is
not configured as a slave.
This change will prevent unintended failovers from happening when network
connectivity is bad. It also allows external actors to clear the slave
configuration from the last remaining server to signal MaxScale that the
server can be used as a master.
maxrows returns empty resultset instead of OK.
The response with coulmndefs is sent then an EOF without flags is added.
Limitations: in case of MULTI_RESULT sets only the first one coulmndefs
is sent with EOF
As before, the cache will be used if there is no ongoing transaction
(includes autocommit being on), or if there is an explicitly read-
only transaction.
In addition, the cache will be used and populated during any other
transaction as long as only pure read statements are executed. After
first non-read statement, the use of the cache is disabled.
The autocommit state is now included in the result returned
from session_trx_is_active(), so it need not be checked separately.
This is preparatory work for MXS-1136 that will change the approach
so that the cache is used and populated in a non readonly transaction
*until* the first non-read statement is encountered.
The thread id is copied to a local variable to avoid having
__tls_get_addr from unnecessarily being called over and over
again. Together that used to amount to some 1% of the execution
time.
Altered the function to assert that the DCB is a backend DCB in addition
to the existing assertions for non-NULL backend reference on function
return.
Move the fetching of the backend reference after the type of the DCB is
inspected in handleError. This removes the need to handle the case where
the returned bref is NULL and the DCB is a client DCB.
They are not particularly useful, they surely are not used
and impose a small cost for every event extracted from the
poll sets.
This commit only removes the maxadmin commands, subsequent
commits will remove the actual code.
These fixes prevent loops turning into eternal loops when
optimizations have been turned on.
The right remedy is to remove the internal locks from hashtable
and use external locks instead.
The `failover_recovery` option allows failed servers to rejoin the
cluster. This should make using MaxScale with two node clusters easier.
One use case for this is when the replication-manager promotes the last
node in the cluster as the master. When this is done, the slave
configuration is cleared and the read-only mode is disabled. Since the
failover requires that the server is not configured as a slave and that it
is not in read-only mode, it is safe to use `failover_recovery` with
replication-manager.
The DECIMAL type was not correctly converted to positive integers. The
0x80 bit was set only for negative numbers when it needed to be XOR-ed for
all values.
The DECIMAL value type is now properly handled in Avrorouter. It is
processed into an Avro double value when before it was ignored and
replaced with a zero integer.
Backported to the 2.0 branch.
There's no point in indexing the file if it hasn't been synced to
disk. Any attempts to index the file will fail if the file still has an
open data block.
If MaxScale is started without the appropriate permissions to the paths
pointed by default values, the debug assertion fails even though the
parameter is valid but not usable.
The random number generator can be initialized when MaxScale's other
systems are being initialized. This removes the need to initialized it
when the function is used for the first time.
NullFilter is a filter module that does nothing, except reports
capabilities as defined in the configuration file. It's purpose
is only to make it simple to benchmark the performance impact
various routing capabilities have.
Note that since getCapabilities() currently does *not* take an
instance pointer as parameter, all NullFilter instances will
report the same capabilities, the ones specified for the last
filter to have been loaded.
Removed unused spinlocks from DCBs, sessions and the MySQL protocol
structs. They were used in a context where only one thread has access to
the structure.
Removed unused member variables from DCBs.
