On Fri, Jul 13, 2018 at 05:49:20AM +0000, Tsunakawa, Takayuki wrote: > David has submitted multiple patches for PG 12, one of which speeds up > pruning of UPDATE/DELETE (I couldn't find it in the current CF, though.) > What challenges are there for future versions, and which of them are being > addressed by patches in progress for PG 12, and which issues are untouched?
Here's an known issue which I'm not sure is on anybody's list: https://www.postgresql.org/message-id/flat/4F989CD8.8020804%40strategicdata.com.au#4f989cd8.8020...@strategicdata.com.au => planning of UPDATE/DELETE (but not SELECT) takes huge amount of RAM when run on parent with many childs. We don't typically have UPDATEs, and those we do are against the child tables; but ran into this last month with a manual query on parent causing OOM. I worked around it, but keep meaning to revisit to see if this changed at all in v11 (very brief testing suggests not changed). Justin
