Re: [HACKERS] pg_dump and thousands of schemas

On Thu, May 31, 2012 at 10:50 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)com> writes:
>> On Thu, May 31, 2012 at 10:31 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>>> I'm not; Jeff Janes is.  But you shouldn't be holding your breath
>>> anyway, since it's 9.3 material at this point.
>
>> I agree we can't back-patch that change, but then I think we ought to
>> consider back-patching some variant of Tatsuo's patch.  Maybe it's not
>> reasonable to thunk an arbitrary number of relation names in there on
>> one line, but how about 1000 relations per LOCK statement or so?  I
>> guess we'd need to see how much that erodes the benefit, but we've
>> certainly done back-branch rearrangements in pg_dump in the past to
>> fix various kinds of issues, and this is pretty non-invasive.
>
> I am not convinced either that this patch will still be useful after
> Jeff's fix goes in, ...

But people on older branches are not going to GET Jeff's fix.

> or that it provides any meaningful savings when
> you consider a complete pg_dump run.  Yeah, it will make the lock
> acquisition phase faster, but that's not a big part of the runtime
> except in very limited scenarios (--schema-only, perhaps).

That is not a borderline scenario, as others have also pointed out.

--
Robert Haas
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