Optionally start or stop an individual worker by passing -w with
the path to the worker config.
Optionally start or stop every worker and the main synapse by
passing -a with a path to a directory containing worker configs.
The "-w" is intended to be used to bounce individual workers proceses.
THe "-a" is intended for when you want to restart all the workers
simultaneuously, for example when performing database upgrades.
SYN-287
This requires that HS owners either opt in or out of stats reporting.
When --generate-config is passed, --report-stats must be specified
If an already-generated config is used, and doesn't have the
report_stats key, it is requested to be set.
