On Sat, Aug 10, 2024 at 10:17:27AM -0500, Nathan Bossart wrote: > On Fri, Aug 09, 2024 at 04:06:16PM -0400, Corey Huinker wrote: >>> Furthermore, most of the callbacks should do almost nothing for a given >>> upgrade, and since pg_upgrade runs on the server, client/server round-trip >>> time should be pretty low. >> >> To my mind, that makes pipelining make more sense, you throw out N queries, >> most of which are trivial, and by the time you cycle back around and start >> digesting result sets via callbacks, more of the queries have finished >> because they were waiting on the query ahead of them in the pipeline, not >> waiting on a callback to finish consuming its assigned result set and then >> launching the next task query. > > My assumption is that the "waiting for a callback before launching the next > query" time will typically be pretty short in practice. I could try > measuring it...
Another option might be to combine all the queries for a task into a single string and then send that in one PQsendQuery() call. That may be a simpler way to eliminate the time between queries. -- nathan
