> iostat -xd 10
>
> have to say about it?
Yes i was indeed maxing out my IO subsystem. % CPU utilization for io
is around 90 percent. I could not notice this earlier because i was
firing CPU load queries from a remote machine hence network overhead
was coming into picture .Thanks a lot for your suggestion.
-Rahila
On Fri, Oct 25, 2013 at 10:34 PM, Scott Marlowe <scott.marlowe@gmail.com> wrote:
> On Fri, Oct 25, 2013 at 8:29 AM, Rahila Syed <rahilasyed90@gmail.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?
>
> To understand recursion, one must first understand recursion.