Ok. So then the data you'll see in Hytop when on z/VM and in some of the Performance Toolkit reports (e.g. FCX112 USER) will show utilization of a logical processor (aka thread), so there isn't a direct correlation to the total Core Utilization from that perspective. Hytop will give you "CPU" time, again think of this as thread time of one of the 2 threads per Core. Hytop breaks down what it calls Total CPU time and then Total Management time. The "Management" time will relate to time spent in z/VM hypervisor or Control Program. So on the FCX112 report, z/VM shows Total and Emul (short for Emulation or Virtual). Emul would be time spent in Linux and its applications and the delta of Total and Emul from Performance Toolkit on FCX112 will map closer to that "Management" time from Hytop.
There is an APAR coming for Performance Toolkit that on z/VM 7.2 (VM66215) that will surface some other counters related to processor usage in SMT-2 environment. I hope that helps. That URL will give some more details. ___________________________________________________________________________________________ Bill Bitner - z/VM Client Focus and Care - 607-429-3286 [email protected] "Making systems practical and profitable for customers through virtualization and its exploitation." - z/VM From: "Mittelstädt, David" <[email protected]> To: [email protected] Date: 10/28/2020 02:29 PM Subject: [EXTERNAL] AW: [EXTERN]-Re: IFL usage of Linux servers Sent by: Linux on 390 Port <[email protected]> Hi Bill, Thanks for the fast replay. I will read the infos in the given URL tomorrow. We are using SMT-2. I ran a q multithreading in z/VM and get back Activated Threads 2 for IFL Core. I'm really interested in the additional information. Thanks. Regards, David -----Ursprüngliche Nachricht----- Von: Linux on 390 Port [mailto:[email protected]] Im Auftrag von Bill Bitner Gesendet: Mittwoch, 28. Oktober 2020 19:05 An: [email protected] Betreff: [EXTERN]-Re: IFL usage of Linux servers Hello David, An important aspect of this is whether you are running SMT-2 or not. If you are, then I recommend you read https://www.vm.ibm.com/perf/tips/smtutil.html for some background as when SMT-2 is on we have to take extra care because in that scenario the word "IFL" is ambiguous between whether we're referencing the Core or the two threads in aggregate, as with SMT-2 many of the measures, but not all, are of a logical processor (aka thread) perspective. If you share whether you're SMT-2 or SMIT-1 or SMT-0 (SMT disabled). I can give you some additional information on interpreting the data. Regards, Bill ___________________________________________________________________________________________ Bill Bitner - z/VM Client Focus and Care - 607-429-3286 [email protected] "Making systems practical and profitable for customers through virtualization and its exploitation." - z/VM From: "Mittelstädt, David" <[email protected]> To: [email protected] Date: 10/28/2020 01:30 PM Subject: [EXTERNAL] IFL usage of Linux servers Sent by: Linux on 390 Port <[email protected]> Hi everyone, I need a little help understanding the values from the z/VM Performance Toolkit and command line tool hyptop. I want to measure the IFL utilization of a z/VM guest running linux from a z/VM or hardware perspective, e.g. linux server A consumes 2 IFL or linux server B consumes 0.5 IFL. We need this information for accounting and forecast purposes. So I used the tool hyptop to get the information of the used cpu, but I'm not sure how to interpret these values correctly. What means the column cpu(%)? Is this the usage of 1 IFL in percent? And is this same value like the one in the z/VM Performance Toolkit %CPU under 21. User resource usage? Is it possible to measure the IFL usage with these values? Or do I need other values? Thanks in advance. Best regards, David Mittelstädt ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www2.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www2.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www2.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www2.marist.edu/htbin/wlvindex?LINUX-390
