Hi, On 2018-09-21 20:38:16 +0300, Sergei Kornilov wrote: > > My first question was whether TWO of them were dead code ... isn't an > > aggressive vacuum to prevent wraparound, and a vacuum to prevent > > wraparound aggressive? > Maybe i am wrong, aggressive autovacuum was your commit. > Message split was in b55509332f50f998b6e8b3830a51c5b9d8f666aa > Aggressive autovacuum was in fd31cd265138019dcccc9b5fe53043670898bc9f > > If aggressive really is wraparound without difference - i think we need > refactor this code, it is difficult have two different flags for same purpose. > > But as far i can see it is possible have aggressive non-wraparound vacuum. > One important difference - regular and aggressive regular can be canceled by > backend,.wraparound autovacuum can not. (by checking > PROC_VACUUM_FOR_WRAPAROUND in src/backend/storage/lmgr/proc.c )
Yes, without checking the code, they should be different. Aggressive is controlled by vacuum_freeze_table_age whereas anti-wrap is controlled by autovacuum_freeze_max_age (but also implies aggressive). Greetings, Andres Freund