Clean up, comments and enhancements. StopWatch lap() didn't mean lap-time, but elapsed time. Changed meaning to lap-time and added split() for split-time.
Cherry-picking the commit from develop since it's also needed for 2.2.
FindASAN did not look for so version 5 and TSAN referred to ASAN. Disable
leak checks for unit tests as some objects always leak, namely servers.
The check for a closed session should never be needed as the core
correctly orders the calls to the module functions. The version numbering
was also not used.
Fixed the incrementation of the query counter so that it uses relaxed
atomic operations.
Replaced SPINLOCK with std::mutex where possible, leaving out the more
complex cases. The big offenders remaining are the binlogrouter and the
gateway.cc OpenSSL locks.
SELECT...FOR UPDATE locks the rows for update, but only if
autocommit==0 or a transaction is active, so in principle even if
it were classified as READ it'd still be sent to master when it
actually matters.
However, even if autocommit==1 and/or no transaction is active, a
slave in read only mode will reject the statement if the user is
subject to the read only restriction (a user with super privileges
is not), which might be considered a server bug. By classifying the
statement as a write, it'll be sent to master and always succeed.
In progress, does not yet overwrite existing code.
The new promotion mechanism automatically retries queries which timed out. It also
handles multimaster situations correctly.
Removed the almost equal comparison and subsequent selection based on historical number of connections.
The effect of it was this: Select the server that has historically, weights or not, been slower. Tested this with 2.2
with maxscale on one server and mariadb:s on two servers with different network lags. The tests with historical
selects were clearly slower.
By default ASAN only reports the errors and doesn't cause the program to
crash. By forcing a SIGABRT, the process will generate a core dump which
causes the test to fail.
Although the act of placing environment variables inside the systemd
service file might seem intrusive, they have no effect on non-ASAN
builds. This appears to be the most convenient and straightforward way of
changing ASAN behavior for testing.
The debug assertion is wrong as the code was changed to prioritize hints
over the router target selection. Also removed the superficial check for
master, slave and relay master states as they are implied by the fact that
the connection is in use.
The readwritesplit transaction management was a large part of the
clientReply function. Moving it into a separate function clarifies the
clientReply function by hiding the comments and details of the transaction
management.
The schemarouter now uses the RWBackend to track the response states. This
fixes the debug assertions that happened with the mxs1113_schemarouter_ps
test.
By splitting the processing and state querying into two separate
functions, the result can be inspected multiple times without triggering
the result processing.
