Power usage differences for PE1850 on FC12
 

Hi everyone,

I've got two servers that are (as far as I'm aware) exactly the same. Both are Dell PE1850 with the same hardware configuration, both are running of FC12, both have the same deamons running (except number 1 runs apache/php and number 2 runs mysqld). The same modules are activated for the kernel. I still have to dubbelcheck the BIOS settings, but they should be all the same.

But the power consumption of both systems is very different! A graph of the power usage is attached to this post, the spikes are reboots. Anyone can help me on finding out which system difference between these systems is causing the power consumption differences?

BR,

Martijn

You say "as far as I'm aware" which makes it sound like you're not sure they are exactly the same.

If you get the Dell Service Tags you can go to Dell's support site and input those Service Tags to determine exactly how they were configured when sent out. I'd look to see if there was difference in CPU type or quantity first as that can definitely affect heat. You could then look for differences in memory and cards in slots. (For example they could both have the same amount of RAM in GB but it might be configured differently with one using all the DIMM slots and the other not.)

Also the location in the rack and the rack's location in the data center could affect temperature. I have one rack dead center my computer room that is constantly running at higher temperatures because of where it is.

Hi,

thanks for the reply. I will visit the datacenter this weekend to compare the BIOS settings. According to the Linux config information CPU's are the same, I'll check the service tags. Thanks for the tip! What the strangest thing to me is, is that the server that uses most power the powergraph doesn't fluctuate. On the 'low power' server the graph does fluctuate. This indicates to me that powermanagement isn't active on the server, but I can't find any setings on OS level. As said, I hope my visit to the data center is going to help. More later...

I don't have any PE1850's to check, but our new T710's have a BIOS setting for "performance" or "power saving"--might be worth checking out.

Come to think of it, I disabled the Intel Speedstep power management/saving options on our PE2900's as we had wicked VM clock skew with it enabled. Perhaps it's the same sort of setting for your PE1850s' Xeons?

You can get the Service Tag by running the dmidecode command in Linux. Most of the PEs I've run that on (with RHEL) report Service Tag information along with others.

Also dmidecode gives you a lot of information useful for comparing the two systems from a hardware standpoint.