If the routing of a session command fails due to problems with the backend
connections, a more verbose error message is logged. The added status
information in the Backend class makes tracking the original cause of the
problem a lot easier due to knowing where, when and why the connection was
closed.
With this bit set, existing connections to a server should not be
closed, but no new connections should be created to the server.
The bits have also slight been rearranged.
- Bits 0 - 15 are now reserved for bits applicable to all servers
- Bits 16 - 31 are monitor specific
Further, the cases whether a server can be connected to and whether
it can be used, but be separated.
Names starting with '@@' can now longer be used in configuration files.
Subsequent commits will prevent such names from being used when objects
are created dynamically.
The class MonitorManager contains monitor-related functions that should not
be called from modules. MonitorManager can access private fields and methods
of the monitor.
Both the replication lag and the message printing state are saved in SERVER,
although the values are mostly used by readwritesplit. A log message is printed
both when a server goes over the limit and when it comes back below.
Because of concurrency issues, a message may be printed multiple times before
different threads detect the new message state.
Documentation updated to explain the change.
The functions stores the current server status to the monitored
server's mon_prev_status and pending_status fields.
To be used at the start of the monitor loop, before the pending
status fields are updated.
First step in the introduction of a MainWorker. When finished, all
routing workers will run in separate threads (currently one runs in
the main thread), and the main worker run in the main thread.
Housekeeper will disappear and to the extent housekeeping tasks are
needed (where applicable they will be changed into delayed calls)
they will be run by the main worker.
Most of the ones still remaining outside are special cases.
Also, removed locking from status manipulation functions as it
has not been required for quite some time.
