PC Processors

[NohatCoder]

As best I can tell, when AMD made the feature default off and optional, all the motherboard manufacturers decided that heir customers didn't need the IBS feature, so they dropped it silently. How do I find the boards that support this feature?

Currently have a 3700X and an MSI B450 GAMING PLUS MAX, that seems to be a dead end because MSI didn't give a **** when other people asked.

[elstaci]

According to Github, IBS is: https://github.com/jlgreathouse/AMD_IBS_Toolkit

This repository contains tools which can be used to access the Instruction Based Sampling (IBS) mechanism in AMD microprocessors from Families 10h, 12h, 15h, 16h, and 17h. IBS is a hardware mechanism that samples a subset of all of the instructions going through a processor. For each sampled instruction, a large amount of information is gathered and saved off as a program runs.

Also from this tech website: https://www.computer.org/csdl/proceedings-article/ispass/2010/05452049/12OmNApLGC2

Abstract

Instruction-Based Sampling (IBS) is a hardware mechanism that improves the accuracy of profiles. IBS is supported by AMD Family 10h processors. The processing pipeline of an AMD Family 10h processor is separated into two loosely coupled phases: A front-end phase that fetches AMD64 instruction bytes and a back-end phase that execute "ops" which issue from decoded AMD64 instructions. An op is an internal, fixed-width instruction which is executed by the pipeline stages in the execution phase. More than one op may issue from an instruction. Due to the decoupling, IBS samples fetches and ops separately, i.e., there are two independent sampling mechanisms. We will concentrate on IBS op sampling in this discussion.

Uprof program use AMD's Code Analyst which includes IBS Feature.

So this IBS feature isn't a Motherboard feature rather a AMD Processor feature which is accessed using programs like Code Analyst or UProf.

[NohatCoder]

It has to be enabled in the BIOS for uProf to work (since 1st generation Ryzen). MSI did not provide this feature in their BIOS. Who did?

[elstaci]

Okay now I understand by a Motherboard supporting IBS. 

I would post your question at AMD Forum's SERVERS GURU which deals with UProf since IBS needs to be enabled in BIOS to work: https://community.amd.com/t5/server-gurus/ct-p/amd-server-gurus

Here is some samples of IBS at Servers Guru using Search:

See what motherboards other Users are using to run UProf program or see if some other Users who use UProf can mention which motherboard they are using.

[elstaci]

This previous thread at AMD Servers Guru suggest that if the option to enable IBS is not in BIOS but it is automatically enabled in Matisse Processors: https://community.amd.com/t5/server-gurus-discussions/ibs-is-disabled-ryzen-5-3600-windows-tuf-b450/...

This involves UProf having been installed:

[NohatCoder · Accepted solution]

Oh, seems like this is just a massive UI failure. uProf says that you have to enable IBS, but you actually have to disable hardware virtualization, and no support anywhere knows this, so the internet is stuffed with misinformation.

[elstaci]

If the problem is using UProf then I advice to post at Servers Guru.  That is where you need to get help with UProf.