causal_reads does not work with servers that update their state via
mechanisms other than the standard replication. In practice this is just
another Galera limitation.
In cases where servers are known to be down on startup, this feature does
more harm than good. Disabling it in these cases would be preferable but
due to how the parameter is used, it is not possible.
The `global` parameter causes the time window defined by the `time`
parameter to be applied at the instance level instead of the session
level. This means that a write from one connection will cause all other
connections to use the master for a certain period of time.
Using a configurable time window for consistency is not good as it is not
absolute and cannot adjust to how servers behave.
One example that demonstrates this is when a slave is normally lagging
behind by less than a second but some event causes the lag to spike up to
several seconds. In this case the configured time window would no longer
guarantee consistency.
Another reason to avoid a "static" time window is the fact taht it
prevents load balancing in the cases where slaves catch up to the master
within time window. This happens when time is configured to a higher value
to avoid inconsistencies at all costs.
Added a test case that verified the feature works.
Generated the new MaxCtrl documentation with the new help output. The help
output now doesn't auto-wrap which causes lines to be longer but it
prevents broken Markdown formatting. It also makes it more readable on
wider terminals.
Generated the new MaxCtrl documentation with the new help output. The help
output now doesn't auto-wrap which causes lines to be longer but it
prevents broken Markdown formatting. It also makes it more readable on
wider terminals.
