Author Topic: Performance metric utilized by the SPECvirt_sc2013 benchmark results  (Read 175 times)

Chelsey165

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As I am very interested in the published SPECvirt_sc2013 benchmark results, I would like to ask for some clarifications regarding the employed SPECvirt_sc2013 performance metric.

According to the FAQ on the SPEC website, SPECvirt_sc2013 is expressed as "SPECvirt_sc2013 @ <5*Number_of_Tiles + Number_of_DBservers> VMs".

As I understand, the right-hand side expression denotes the number of VMs utilized on the virtualized SUT (System Under Test), at peak performance.

However, examining for example the benchmark results for Hangzhou H3C Technologies Co., Ltd UIS R390, the score is SPECvirt_sc2013 638.6 @ 37 VMs.

The physical host has a processor with 32 threads, i.e. logical processors (16 cores x 2 threads per core). The VMs on the host are configured as follows: 1. Web Server VM: 2 vCPUs 2. App Server VM: 3 vCPUs 3. Mail Server VM: 1 vCPU 4. Batch Server VM: 1 vCPU 5. Infraserver VM: 1 vCPU

Total: 8 vCPUs

All of the above VMs are required for the execution of 1 tile. Furthermore, for each set of 4 tiles, a DB server VM is required, which is configured as follows: - DB Server VM: 6 vCPUs

According to the benchmark result, at peak performance 37 VMs are utilized, of which 2 are DM Server VMs, which means:

7 tiles * (Web Server VM + App Server VM + Mail Server VM + Batch Server VM + Infraserver VM) + 2 * DB Server VM

Hence 7 * 8 vCPUs + 2 * 6 vCPUs = 68 vCPUs are utilized at peak performance.

But considering that 1 vCPU = 1 logical processor on the physical host, how is it possible that 68 vCPUs are utilized when the capacity of the physical processor is only 32 logical processors?

I guess I am missing something here, so I would greatly appreciate it if you could shed some light on this matter. I could not find anything that could help me explain it on the FAQ section of the SPEC website.
« Last Edit: April 18, 2022, 01:26:20 PM by lroderic »

lroderic

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>But considering that 1 vCPU = 1 logical processor on the physical host...

This is incorrect. One vCPU is not equal to one logical processor. One logical processor can support many vCPUs. That's why it's called virtualization.
« Last Edit: April 15, 2022, 12:25:26 PM by lroderic »