Re: PostgreSQL pgbench performance regression in 2.6.23+

From: Greg Smith
Date: Fri May 23 2008 - 14:46:54 EST


On Fri, 23 May 2008, Anton Petrusevich wrote:

Excuse me for interrupting you, but am I getting this right: to run
effectively PostgreSQL with an active web app on the server a "system
administrator Joe" has to know about batch scheduling?

That's not true. The problem here is specifically with the pgbench program, which is a simple benchmarking tool included with PostgreSQL. pgbench already had known scalability problems due to its inefficient design and the new scheduler really doesn't play well with it by default. It's the pgbench program that needs the batch scheduling, not the database processes.

pgbench is certainly not representative of web application performance, and it wouldn't be the first time there was some OS tweaking required to get good results from such an artificial benchmark.

--
* Greg Smith gsmith@xxxxxxxxxxxxx http://www.gregsmith.com Baltimore, MD
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