On Thu, Nov 02, 2017 at 09:13:05PM +0000, Rhhh Lin wrote: > Yes, it may be an issue with the index, but I'd like to have some evidence > towards that before dropping and recreating (It does not appear that bloat is > a problem here or dead tuples either). Why do you say those aren't an issue? Just curious. Have you vacuum or reindexed (or pg_repack) ? How large are the table and index? \dt+ and \di+ > The reason I am very suspect of the timestamp column makeup is that if I > remove that predicate from the EXPLAIN command and the actual query, both > complete within seconds without issue. So I do know where the issue is (I > just dont know what the issue is!). It could be that you're hitting selfuncs.c:get_actual_variable_range() and the extremes of the index point to many dead tuples (as I see Tom suggests). You could strace the backend and see if it's reading (or writing??) consecutively (hopefully with ample OS readahead) or randomly (without). Justin -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
