The additions into the server.h header used C++ language which caused C
programs to fail to compile. Moved the implementation of the EMAverage
class into the private Server class in the server.hh header and exposed it
via functions in the server.h header. Also temporarily moved
almost_equal_server_scores into the public server.hh as there is no
service.hh header.
See script directory for method. The script to run in the top level
MaxScale directory is called maxscale-uncrustify.sh, which uses
another script, list-src, from the same directory (so you need to set
your PATH). The uncrustify version was 0.66.
The math becomes simpler when the weight is inverted, i.e. a simple multiplication
to get the (inverse) score. Inverse weights are normalized to the range [0..1] where a lower
number is a higher weight,
The enum select_criteria_t is used to provide a std::function that takes the backends
as vector (rather than the prior pairwise compares) and returns the best backend.
The main piece of code, slave selection (backend_cmp_response_time), uses the available
method of pair-wise comparison of slaves. This will be changed to selection using all
available slaves, along with removal of hard coded values.
This is to support calculating the average from a session, and the slave selection criteria to be able to route based on averages. This commit, like the next one, have TODOs which you should feel free to comment on. Undecided things.
Given that worker.hh was public, it made sense to make routingworker.hh
public as well. This removes the need to include private headers in
modules and allows C++ constructs to be used in C++ code when previously
only the C API was available.
The mxs::rworker_local<T> is a convenience type that provides fast read
access with thread-safe updates. It is intended to be used with data that
is read often but updated rarely e.g. configuration data for routers.
By storing the data gathere by readwritesplit inside the session, the
protocol will be aware of the state of the LOAD DATA LOCAL INFILE
execution. This prevents misinterpretation of the data which previously
led to closed connections, effectively rendering LOAD DATA LOCAL INFILE
unusable.
This change is a temporary solution to a problem that needs to be solved
at the protocol level. The changes required to implement this are too big
to add into a bug fix release.
No longer depends on monitor events as the other operations do not
either. The active_event/new_event detection was removed, as these
only protect against a rare situation. A similar feature which
protects all the cluster modifications will be implemented later.
The maxscale_is_shutting_down function is used to detect when MaxScale
should stop. This fixes a race condition in the code where the workers has
not yet been initialized but a termination signal has been received. It
also replaces the misuse of the service_should_stop variable with a proper
function.
qc_thread_init() must now explicitly be called in every thread
and not just in other threads but the one where qc_process_init()
is called.
This change was caused by QC_INIT_SELF initialization actually
being performed in query_classifier.cc. Before this change, there
actually was a leak in the routing worker running in the main
thread, the query classification cache was created twice.
The print_log_n_stderr function used to implicitly initialize the log
manager. As this is no longer done, no logging must be done before the log
manager is initialized.
The monitor JSON is now more closely inspected before the actual monitor
is allocated. This prevents creation of monitors without credentials which
was previously possible.
The monitor alteration was also changed to stop and start the monitor only
once instead of stopping and starting after each parameter
modification. This prevents multi-parameter updates from failing due to
monitors seeing a partial set of the new values. Currently only the
`replication_user` and `replication_password` parameters could cause this.
If a service was created at runtime, it would be in the Allocated state
until it was stopped. The serviceStart function isn't necessary from a
functional point of view (a new service cannot have listeners that need
starting) but it does set the correct state and it's the "right" thing to
do.
Monitors created via the REST API that were started and configured
successfully should also be started. This removes the extra step of
starting the monitor after creating it.
The executable name of the PID is now checked to be maxscale. This fixes
the problem where MaxScale would refuse to start if a stale PID file had a
PID of a process that's not a MaxScale process.
Enabling it will give a performance improvement and it offloads work from
the CPU. This leads to better and more complete utilization of system
resources.
The master server of a monitor can now be extracted with the
mon_get_external_master function. It uses the REST API to find a master
server in the set of servers monitored by a monitor.
The test does a request and prints the responses. It is done to see that
the functionality works. Also added a timeout of 10 seconds to both the
connection and data transfer phases.
Services, monitors and filters all use the parameters for object
serialization. This means that when the object is created, the module
parameter must be in the parameter list.
