Backpatch-through: 11
We had a little bit of coverage here thanks to e2f65f425, but not enough; notably, autoprewarm wasn't exercised at all. Dong Wook Lee, with help from Julien Rouhaud and myself Discussion: https://postgr.es/m/20220629053812.mifmdrch5iuasg2s@home-desktop
e2f65f425