On Sun, 2025-01-12 at 14:54 +1300, David Rowley wrote: > While I do understand the desire to reduce Hash Agg's memory usage, > has this really been through enough performance testing to be getting > committed?
Perhaps not. I'm going to revert it while we sort it out, and hopefully we can find a solution because it's a substantial memory savings. > I wonder if there's some other better way of doing this. Would it be > worth having some function like ExecCopySlotMinimalTuple() that > accepts an additional parameter so that the palloc allocates N more > bytes at the end? Maybe it's worth hunting around to see if there's > any other executor nodes that could benefit from that infrastructure. That would be convenient, but doesn't seem like a great separation of responsibilities. Perhaps some API that separated the length calculation, and accepted a caller-supplied buffer? Regards, Jeff Davis