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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Munro <thomas.munro@enterprisedb.com>
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Subject: Re: pgsql: Add parallel-aware hash joins.
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Comments: In-reply-to Thomas Munro <thomas.munro@enterprisedb.com>
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Thomas Munro <thomas.munro@enterprisedb.com> writes:
> On Thu, Dec 28, 2017 at 3:32 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Aside from the instability problems, I'm pretty unhappy about how much
>> the PHJ patch has added to the runtime of "make check".  I do not think
>> any one feature can justify adding 20% to that.  Can't you cut down the
>> amount of data processed by these new test cases?

> Isn't that mostly because of the CV livelock problem?

Hm, maybe.  I quoted the 20% figure on the basis of longfin's reports,
not prairiedog's ... but it might be seeing some of the livelock effect
too.

> So without the effects of that bug it's only taking 2.4% longer than
> commit fa330f9a.  Is that acceptable for a feature of this size and
> complexity?  I will also look into making the data sets smaller.

That sounds better, but it's still worth asking whether the tests
could be quicker.

			regards, tom lane