Whether or not a session should retain its statements is now
a property of the session. This in preparation for making the
whole functionality a property that can be enabled and disabled
at runtime, of the service.
As the router is the only one that knows what backends a particular
statement has been sent to, it is the responsibility of the router
to keep the session bookkeeping up to date. If it doesn't we will
know what statements a session has received (provided at least some
component in the routing chain has RCAP_TYPE_STMT_INPUT capability),
but not how long their processing took. Currently only readwritesplit
does that.
All queries are stored and not just COM_QUERY as that makes the
overall bookkeeping simpler; at clientReply() time we do not need to
know whether or not to bookkeep information, we can just do it.
When session information is queried for, we report as much information
we have available.
The main class was getting unwieldly and too general. Dividing the fields
helps adding support for other operation types.
This commit leaves most data duplicated, later commits clean up the affected code.
The old 'passwd' parameter is now converted to the 'password' parameter
and a warning about its deprecation is logged. This keeps the mandatory
parameter detection functional while still allowing old-style
configurations to be used.
The causal_reads_timeout default value is too long when considering the
behavioral changes that MXS-2141 introduced. With a 10 second default
value, a result is returned to the client in a reasonable amount of time.
With causal_reads enabled, the query would return with an error if the
slave was not able to catch up to the master fast enough. By automatically
retrying the query on the master, we're guaranteed that a valid result is
always returned to the client.
The test description talks about putting the master into maintenance mode
but it spends most of the time putting slaves into maintenance mode. To
make the test more precise (and fast) the test can be reduced to blocking
the most often used slave and the master. The iteration count can also be
lowered from five to two to get at least two cycles of maintenance mode.
This is currently disallowed for the server parameter, as the value could be
read/written concurrently. The monitor parameter can be changed since the
monitor is stopped during write.
The removed statistics variables have no meaning anymore and
were not updated.
Decided to simply drop the variable from the JSON output. It
gets far too rigid if fields of objects cannot be changed without
bumping the REST-API version.
Separated mmmon and ndbclustermon from the list of supported modules into
their own legacy section. Added a warning about the deprecation to the
relevant documents.
Also added the csmon link to the documentation contents.
Added the csmon monitor which supports both old and new ColumnStore
servers. As older server versions aren't able to express their role, the
master needs to be designated by the user. When a ColumnStore version is
released that supports the mcsSystemPrimary() function, the master can be
automatically found.
