On 15 September 2010 12:05, Tobias Brox <tobixen@xxxxxxxxx> wrote: > Recently we've frequently encountered issues where some simple selects > (meaning, selects doing an index lookup and fetching one row) have > become stuck for several minutes. Apparently all requests on one > exact table gets stuck, all requests not related to said table are > going through without any problems. Now I've set up all kind of logging regarding locks, so it seems like we're having issues that aren't lock-related. I just did a bit of research into one situation today. All while having this problem, there was one heavy query running in parallell ... not sure if that's relevant. Then comes one query that requires a seq scan on the problem table (that won't happen again - I just added a new index). Four seconds later comes another query requiring a simple index lookup. Still more queries comes in, most of them simple index lookups, but on different indexes. After one minute there are 25 queries in the pg_stat_activity view towards this table. It's not a particularly huge table. Moments later all 25 queries have been executed. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
