Oracle 5.0 Reference Manual page 2661

Mysqlnd replication and load balancing plugin (mysqlnd_ms)
Statistics are aggregated for all connections and all storage handler. It is not possible to tell how much
queries originating from mysqli,
data values.
Parameters
This function has no parameters.
Return Values
Returns if the PHP configuration directive
NULL
Otherwise, returns array of statistics.
Array of statistics
Statistic Description
The semantics of this statistic has changed between 1.0.1 - 1.1.0.
use_slave
The meaning for version 1.0.1 is as follows. Number of statements
considered as read-only by the built-in query analyzer. Neither
statements which begin with a SQL hint to force use of slave nor
statements directed to a slave by an user-defined callback are
included. The total number of statements sent to the slaves is
use_slave
PECL/mysqlnd_ms 1.1.0 introduces a new concept of chained filters.
The statistics is now set by the internal load balancing filter. With
version 1.1.0 the load balancing filter is always the last in the filter
chain, if used. In future versions a load balancing filter may be followed
by other filters causing another change in the meaning of the statistic.
If, in the future, a load balancing filter is followed by another filter
it is no longer guaranteed that the statement, which increments
use_slave, will be executed on the slaves.
The meaning for version 1.1.0 is as follows. Number of statements
sent to the slaves. Statements directed to a slave by the user filter
(an user-defined callback) are not included. The latter are counted by
use_slave_callback.
The semantics of this statistic has changed between 1.0.1 - 1.1.0.
use_master
The meaning for version 1.0.1 is as follows. Number of statements
not considered as read-only by the built-in query analyzer. Neither
statements which begin with a SQL hint to force use of master
nor statements directed to a master by an user-defined callback
are included. The total number of statements sent to the master is
use_master
PECL/mysqlnd_ms 1.1.0 introduces a new concept of chained filters.
The statictics is now set by the internal load balancing filter. With
version 1.1.0 the load balancing filter is always the last in the filter
chain, if used. In future versions a load balancing filter may be followed
by other filters causing another change in the meaning of the statistic.
If, in the future, a load balancing filter is followed by another filter
it is no longer guaranteed that the statement, which increments
use_master, will be executed on the slaves.
The meaning for version 1.1.0 is as follows. Number of statements
sent to the masters. Statements directed to a master by the user filter
(an user-defined callback) are not included. The latter are counted by
use_master_callback.
PDO_MySQL
+
use_slave_sql_hint
+
use_master_sql_hint
2641
or API calls have contributed to the aggregated
mysql
mysqlnd_ms.enable
+ use_slave_callback.
+ use_master_callback.
has disabled the plugin.
Version
Since 1.0.0.
Since 1.0.0.