On 2020-May-06, Peter Geoghegan wrote: > Also, do we really want to skip summarization of BRIN indexes? This > cleanup is rather dissimilar to the cleanup that takes place in most > other AMs -- it isn't really that related to garbage collection (BRIN > is rather unique in this respect). I think that BRIN might be an > inappropriate target for "index_cleanup off" VACUUMs for that reason. > > See the explanation of how this takes place from the docs: > https://www.postgresql.org/docs/devel/brin-intro.html#BRIN-OPERATION
Good question. I agree that BRIN summarization is not at all related to what other index AMs do during the cleanup phase. However, if the index_cleanup feature is there to make it faster to process a table that's nearing wraparound hazards (or at least the warnings), then I think it makes sense to complete the vacuum as fast as possible -- which includes not trying to summarize it for brin indexes. -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services