In case an array of cache rules is provided, we will only store
references to the objects in the array. Consequently, the counts of
the borrewed references to the objects must be increased, and the
reference count of the array itself decreased.
If a session command produces a different result on the slave than it did
on the master, a warning is logged. This warning now also logs the query
that was being executed to make investigation of the problem easier.
Previously schemarouter only mapped databases to the servers
they were resided on. Now all the tables are also mapped to allow the
router to route queries to the right server based on the tables used in
that query.
The stacktrace generation is now a part of the maxbase library. The code
is the same code that was previously defined in gateway.cc as a part of
MaxScale.
The only way to cleanly separate the maxutils library from the MaxScale
CMake project is to make it a standalone CMake project. With the help of
ExternalProject, it should be relatively easy to use.
Backend::execute_session_command would use the overridden write method
instead of the Backend::write method that it intended to use. This caused
session commands that did not expect a response to be in a state that
expected a result.
Also fixed RWBackend::write pass the response_type value to
Backend::write.
Look for the expected message several times, with short sleeps in
between. That way we will not sleep more than necessary, yet will
not immediately give up either.
Going the belt-and-suspenders way of both sleeping and waiting for the
moitor should make sure MaxScale has at least some time to start up, query
the servers and do a single iteration of monitoring.
If the service user does not have adequate grants to the mysql tables, the
legacy query is used. This prevents an upgrade failure when the user was
lacking the new privileges.
The user now requires SELECT privileges on the mysql.roles_mapping
table.
Currently this is a mandatory grant but it needs to be made into an
optional requirement. This allows upgrades from 2.2.9 to 2.2.10 without
needing new grants.
The cache filter walks through the resultset in order to detect
when the resultset ends. That is, it reads each packet header as
they arrive.
In case the resultset is large, the cache will have to read several
packet headers. That it does using gwbuf_copy_data(). However, as that
was done using the first received GWBUF as the starting point, it meant
that in gwbuf_copy_data() the buffer chain was walked over and over
and over again, with a significant performance hit as the result.
Now we separetely store the last buffer received, and the the starting
offset of it. That way there will be no buffer chain walking.
As this is a common problem, GWBUF could cache the offset of the tail,
thus removing the performance penalty if you read from an offset that
happens to be in the tail. However, it's better to do that as a part
of a general overhaul of GWBUF.
If the server sends a server shutdown error, it is safe for readwritesplit
to ignore it. When the TCP connection is closed, the router error handling
will discard the connection, optionally replacing it.
