CPU frequency scaling

[debfawn]

Howdy,

I am trying to add a node to my Vertica cluster. I noticed in the output of the upgrade_vertica script has the following statements:

CPU frequency scaling is enabled. This may adversely affect the performance of your database.
Vertica recommends that cpu frequency scaling be turned off or set to 'performance'

Do I need to do this? If so, how can I?

Thank you!

[thatsafunnyname]

See:
https://my.vertica.com/docs/6.1.x/HTML/ ... #18481.htm
it is very much dependent on the hardware (CPUs and BIOS (you may want to check BIOS release notes for any fixes for C-states , C1E , P-states , Dynamic frequency scaling , CPU throttling , Dynamic voltage scaling , Advanced Configuration and Power Interface (ACPI) settings), and the OS distribution and (kernel) version.

[doug_harmon]

Run this for an assessment of what your CPU's are capable of compared to their actual performance. If the cpu_frequency_mhz is lower than what the specs are calling for then you'll want to talk to your linux admin about disabling CPU frequency scaling.

Code: Select all

select node_name, processor_id, model_name, cpu_frequency_mhz, count(*) as Qty
from dc_cpu_info
group by 1,2,3,4
order by 1,2,3,4
limit 10000;

Results:

Code: Select all

node_name         processor_id  model_name                                       cpu_frequency_mhz  Qty   
----------------  ------------  -----------------------------------------------  -----------------  ----  
v_abcde_node0001  0             Intel(R) Xeon(R) CPU           X8690  @ 3.47GHz  3465000            2264  
v_abcde_node0001  1             Intel(R) Xeon(R) CPU           X8690  @ 3.47GHz  3465000            2264  
v_abcde_node0001  10            Intel(R) Xeon(R) CPU           X8690  @ 3.47GHz  3465000            2264 

[debfawn]

Thanks for the reply guys! I see how to make the change now. I do have one more question though. Do you think this setting matters for a cluster made up of virtual machines?