On Thu, Mar 23, 2017 at 2:47 PM, Pavan Deolasee <pavan.deola...@gmail.com> wrote: > It's quite hard to say that until we see many more benchmarks. As author of > the patch, I might have got repetitive with my benchmarks. But I've seen > over 50% improvement in TPS even without chain conversion (6 indexes on a 12 > column table test).
This seems quite mystifying. What can account for such a large performance difference in such a pessimal scenario? It seems to me that without chain conversion, WARM can only apply to each row once and therefore no sustained performance improvement should be possible -- unless rows are regularly being moved to new blocks, in which case those updates would "reset" the ability to again perform an update. However, one would hope that most updates get done within a single block, so that the row-moves-to-new-block case wouldn't happen very often. I'm perplexed. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
