topic RAPL DRAM power limit in Software Tuning, Performance Optimization & Platform Monitoring

RAPL DRAM power limit

Saeid_B_ — Tue, 17 Feb 2015 22:07:23 GMT

Hi,

I am currently working on using RAPL to set power caps on both CPUs and DRAMs. I have a dual socket machine (motherboard model: supermicro X9DRL-3F/iF) ,and with Intel(R) Xeon(R) CPU E5-2690 v2 CPUs.

I can successfully monitor power and set power cap on any component except DRAM. More specifically, I can monitor the DRAM power but cant write anything into register "MSR_DRAM_POWER_LIMIT". Also I tried to set unlock bit, but it didn't work either. (corresponding bits show that this register is locked and disabled)

Moreover, BIOS option for DRAM RAPL is set to "mode 1". I've tried other modes as well but no changes happens.

Do you know any idea how to cap the DRAM domain? or tell me what I am doing wrong in this process?

Thanks in advance

I'm still waiting for someone

Saeid_B_ — Mon, 02 Mar 2015 02:10:37 GMT

I'm still waiting for someone that could help me. Any help or suggestion will be appreciated.

Hi,

Huazhe_Z_ — Tue, 03 Mar 2015 00:53:58 GMT

Hi,

I am having exactly the same problem(same hardwares(cpu, motherboard)). If the issue is the motherboard, can someone tell me a functional motherboard to cap DRAM power using RAPL? any help would be appreciated! Thank you!

Huazhe

Hello Saeid

Patrick_F_Intel1 — Fri, 06 Mar 2015 16:05:49 GMT

Hello Saeid

It looks like the bios has set the lock bit in MSR_DRAM_POWER_LIMIT. You probably need a new bios (at least) to allow you to change the MSR. I'm just speculating but it might be locked because the board doesn't support changing the DRAM power.

Pat