Postgres Pro
Downloads
Home   >   mailing lists

Re: Recursive query performance issue - Mailing list pgsql-performance

From Pavel Stehule
Subject Re: Recursive query performance issue
Date
Msg-id CAFj8pRB5fmPqc4DZyWwJqkdMM8OhnZJBivxuf46hR5UYEQfi6Q@mail.gmail.com
Whole thread Raw
In response to Recursive query performance issue  (Jamie Koceniak <jkoceniak@mediamath.com>)
Responses Re: Recursive query performance issue  (Jamie Koceniak <jkoceniak@mediamath.com>)
List pgsql-performance
Tree view
Hi



2015-10-20 19:34 GMT+02:00 Jamie Koceniak <jkoceniak@mediamath.com>:

Version:

-----------------------------------------------------------------------------------------------

PostgreSQL 9.1.14 on x86_64-unknown-linux-gnu, compiled by gcc (Debian 4.7.2-5) 4.7.2, 64-bit

 

Query Plan

http://explain.depesz.com/s/4s37

 

Normally, this query takes around 200-300 ms to execute.

However when several queries are run concurrently, query performance drops to 30-60 seconds.

 


there can be few reasons:

1. locking - are you sure, so your queries don't wait on locks?

2. issues with cache stability - is there high IO load? You can try to increase effective_cache_size (or decrease if you have not enough memory)

Regards

Pavel
 

 


pgsql-performance by date:

Previous
From: Jamie Koceniak
Date:
Subject: Recursive query performance issue
Next
From: Merlin Moncure
Date:
Subject: Re: Recursive query performance issue