MessageQueue encapsulates a message queue built on top of a
pipe. The message queue needs a handler for receiving messages
and must be added to a worker for pumping messages through the
pipe.
Each Worker will have an instance of MessageQueue.
Now the epoll instance of the Worker is used when polling. The
work is still done in poll.cc and the worker provides the descriptor
and thread id.
The comments of poll_waitevents() have been removed; they were not
accurate anymore so better to let the code speak for itself.
And add the Worker header...
The epoll instance is not used yet, but the common creation of epoll
instances in poll.cc will be removed and the epoll instances of each
worker used instead.
This is the first step in turning the worker mechanism and everything
around it into a set of C++ classes. In this change, the original C
API is still present, but in subsequent changes that will be removed.
The shutdown is now performed so that a shutdown message is
sent to all workers. When the workers receive that message, they
turn on a shutdown flag, which subsequently is checked in the poll
loop.
This number (defaults to 1) sets how many times mon_connect_to_db
will try to connect to a backend before returning an error. Every
connection attempt may take backend_connect_timeout seconds to
complete.
Also refactored code a bit. Renamed mon_connect_to_db to
mon_ping_or_connect_to_db, since it does not connect if the connection
is already alive.
The contents of the existing filter.cc was copied into filter.c that
subsequently was renamed to filter.cc.
The way the session is called as the last filter in the filter chain
is really dubious and ought to be rearranged so that the blind casting
of a session to a filter and back is not needed.
For the general case, regex matching simply will not do. The
regex becomes so hairy so it turns write-only, i.e. unmaintainable.
Regex matching is also slower than a handwritten custom parser.
TheBoundaryMatcher is not updated as it is likely it will be removed
altogether. A regex that accepts comments in all relevant places becomes
so hairy it is unmaintainable. It seems that the only working solution
would be to first remove all comments and then perform the regex.
A class capble of detecting statements that change the transaction
state and autocommit mode. The detection is done using regexes.
There is still some expanding and optimization to be done.
A class capble of detecting statements that change the transaction
state and autocommit mode.
There are still some expansion and optimization to be done.
Transaction boundaries can now be detected using regexes.
All else being equal, it gives a 10% performance improvement
compared to qc-based detection.
In a subsequent change, mysql_client.c will be modified to use
qc_get_trx_type_mask() instead of qc_get_type_mask().
Currently the use of regex matching is turned on using an
environment variable. That will change.
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.
This header defines some general functions and maxscale main() return
values. Most of it is still public, but there were some functions
which were moved to a core header.
Moved some typedefs to router.h and server.h, changed a few
constants to these enums. Renamed some types in config.h to
remove "Gateway".
There are still some functions in the public header which are
only used in core, but they seem to fit the theme of public functions
so were not moved.
When the relay master or external slave states change, they should be
ignored in the current implementation. When the relay master and slave of
external master events are added, the events can be enabled.
