Re: Increasing CPU usage of PostgreSQL

On Fri, Oct 25, 2013 at 8:29 AM, Rahila Syed <rahilasyed90(at)gmail(dot)com> wrote:
> Hello All,
>
> I am using jdbcrunner-1.2 to run PostgreSQL performance tests. For
> certain tests, i need to increase the CPU usage of the servers
> especially at user level.
> I tried using both tpcc and tpcb load with scale factor of 100. Even
> after setting the number of client connections as high as 420, I am
> unable to achieve high CPU usage. It is hardly 3 percent. I think this
> is because most of the client connections are idle.
> The tpcc and tpcb transactions seem to be consuming very less CPU.
>
> In postgresql.conf file, I have lowered checkpoint segments to 1 in
> order to overwhelm the server with checkpoints but no significant
> increase in iowait of the CPU.
>
> Can somebody suggest a better idea to load PostgreSQL servers to
> increase CPU usage.?
>
> Configurations of my machine is:
>
> Processors: Xeon E5-2650 Processor Kit
> Intel® Xeon ® Processor E5-2650 (2 GHz, 8C/16T,
> 20 MB) * 2 nos
>
>
> RAM : 32GB DDR3-1600 REG Memory Kit
> 8x 4GB Registered ECC DIMM, DDR3L-1600(PC3L-12800)
>
> HDD: 450GB 10K Hot Plug 2.5-inch SAS HDD * 8 nos
> 1 x 450 GB SAS HDD, 2.5-inch, 6Gb/s
>
> Disk Speed : 10,000 RPM
>
> RAID Controller (512MB, RAID 0/1)

My guess is that you're maxing out your IO subsystem long before
you're maxing out CPU. What does

iostat -xd 10

have to say about it?

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