Hi, On 2019-03-04 16:28:40 -0500, Tom Lane wrote: > Andres Freund <and...@anarazel.de> writes: > > I don't buy this. I think e.g. redisgning the way we represent > > targetlists would be good (it's e.g. insane that we recompute > > descriptors out of them all the time), and would reduce their allocator > > costs. > > Maybe we're not on the same page here, but it seems to me that that'd be > addressable with pretty localized changes (eg, adding more fields to > TargetEntry, or keeping a pre-instantiated output tupdesc in each Plan > node). But if the concern is about the amount of palloc bandwidth going > into List cells, we're not going to be able to improve that with localized > data structure changes; it'll take something like the patch I've proposed.
What I'm saying is that it'd be reasonable to replace the use of list for targetlists with 'list2' without a wholesale replacement of all the list code, and it'd give us benefits. > I find it interesting that you get different results. What I reported weren't vanilla pgbench -S results, so there's that difference. If measure the DO loop based test I posted, do you see a difference? Greetings, Andres Freund
