Re: [PATCH] pg_dump: lock tables in batches

Andres Freund <andres@anarazel.de> writes:
> On 2022-12-07 10:44:33 -0500, Tom Lane wrote:
>> I have a strong sense of deja vu here.  I'm pretty sure I experimented
>> with this idea last year and gave up on it.  I don't recall exactly
>> why, but either it didn't show any meaningful performance improvement
>> for me or there was some actual downside (that I'm not remembering
>> right now).

> IIRC the case we were looking at around 989596152 were CPU bound workloads,
> rather than latency bound workloads. It'd not be surprising to have cases
> where batching LOCKs helps latency, but not CPU bound.

Yeah, perhaps.  Anyway my main point is that I don't want to just assume
this is a win; I want to see some actual performance tests.

> I wonder if "manual" batching is the best answer. Alexander, have you
> considered using libpq level pipelining?

I'd be a bit nervous about how well that works with older servers.

            regards, tom lane