On 03/15/2015 09:43 AM, Scott Marlowe wrote:
* Consider installing perf (linux-utils-$something) and doing a systemwide profile. 3.2 isn't the greatest kernel around, efficiency wise. At some point you might want to upgrade to something newer. I've seen remarkable differences around this.
Not at some point, now. 3.2 - 3.8 are undeniably broken for PostgreSQL.
That is an understatement. Here's a nice article on why it's borked: http://www.databasesoup.com/2014/09/why-you-need-to-avoid-linux-kernel-32.html Had a 32 core machine with big RAID BBU and 512GB memory that was dying using 3.2 kernel. went to 3.11 and it went from a load of 20 to 40 to a load of 5.
Yep, I can confirm this behavior.
You really should upgrade postgres to a newer major version one of these days. Especially 9.2. can give you a remarkable improvement in performance with many connections in a read mostly workload.
Seconded. JD -- Command Prompt, Inc. - http://www.commandprompt.com/ 503-667-4564 PostgreSQL Support, Training, Professional Services and Development High Availability, Oracle Conversion, @cmdpromptinc Now I get it: your service is designed for a customer base that grew up with Facebook, watches Japanese seizure robot anime, and has the attention span of a gnat. I'm not that user., "Tyler Riddle" -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance