Re: Out of Memory errors are frustrating as heck!

2019-10-06 Thread Tomas Vondra
On Fri, Aug 23, 2019 at 09:17:38AM -0400, Gunther wrote: Hi all, I am connecting to a discussion back from April this year. My data has grown and now I am running into new out of memory situations. Meanwhile the world turned from 11.2 to 11.5 which I just installed only to find the same out of

Re: Out of Memory errors are frustrating as heck!

2019-10-06 Thread Tomas Vondra
On Sat, Aug 24, 2019 at 11:40:09AM -0400, Gunther wrote: Thanks Tom, yes I'd say it's using a lot of memory, but wouldn't call it "leak" as it doesn't grow during the 30 min or so that this query runs. It explodes to 4GB and then stays flat until done. Well, the memory context stats you've s

Re: Delete huge Table under XFS

2019-10-06 Thread Tomas Vondra
On Thu, Sep 19, 2019 at 07:00:01PM +0200, Joao Junior wrote: A table with 800 gb means 800 files of 1 gb. When I use truncate or drop table, xfs that is a log based filesystem, will write lots of data in its log and this is the problem. The problem is not postgres, it is the way that xfs works

Re: Slow PostgreSQL 10.6 query

2019-10-06 Thread Tomas Vondra
On Tue, Oct 01, 2019 at 11:42:33PM +1000, Behrang Saeedzadeh wrote: Thanks. That eliminated the bottleneck! Any ideas why adding ORDER BY to the subquery also changes the plan in a way that eliminates the bottleneck? IIRC the ORDER BY clause makes it impossible to "collapse" the subquery into

Re: Query went slow all of sudden. ON V 11.3

2019-10-06 Thread Tomas Vondra
On Fri, Oct 04, 2019 at 07:28:54PM +0530, nikhil raj wrote: Hi Justin, Its been executing for 35 + mins due to statement time out its getting canceled. Well, without a query plan it's really hard to give you any advice. We need to see at least EXPLAIN output (without analyze) to get an idea o