the manual says that the SQT and the DSI both do the
ordering of the transactions by commit order. why is it
necessary to do this twice?

also it is said the when the Distributor is disabled for a
Warm Standby, the SQT is also automatically disabled. so who
does the ordering by commit order in for a Warm Standby? the
DSI?

or is my first question wrong? the DSI does the ordering for
Warm Standbys and the SQT for non Warm Standbys?

appreciate the clarification.