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On 3/28/20 9:24 AM, tuxic@××××××.de wrote: |
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> On 03/28 05:59, Mark Knecht wrote: |
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>> On Fri, Mar 27, 2020 at 10:58 PM <tuxic@××××××.de> wrote: |
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>>> |
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>>> On 03/27 11:51, Mark Knecht wrote: |
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>>>> On Fri, Mar 27, 2020 at 11:11 AM <tuxic@××××××.de> wrote: |
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>>>>> |
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>>>>> On 03/27 06:04, Andrea Conti wrote: |
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>>>>>> Hello, |
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>>>>>> |
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>>>>>>> Thread(s) per core: 1 <<<<< |
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>>>>>>> Does my CPU hyperthread? |
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>>>>>> |
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>>>>>> Definitely not. |
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>>>>>> |
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>>>>>> Your kernel config is fine, chances are hyperthreading (aka "SMT |
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>> mode") |
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>>>> is |
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>>>>>> disabled in your BIOS settings. |
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>>>>>> |
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>>>>>> andrea |
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>>>>>> |
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>>>>> |
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>>>>> Hi Andrea, |
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>>>>> |
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>>>>> I checked that: The BIOS setting was set to use hyperthreading. |
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>>>>> |
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>>>>> But "Number of cores" was set to six. I changed that to 12 and |
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>>>>> Voila! I got two threads per core. |
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>>>>> |
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>>>>> I think "Number of cores" is a little misleading, since there |
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>>>>> are six physical cores (not threads) with a RYZEN 5. |
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>>>>> |
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>>>>> I feeling not that comfortable with this solution. |
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>>>>> |
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>>>>> Is there any way to check for the validity of this setting |
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>>>>> beside a tool, which prints a "2" after the word "threads" ;) ? |
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>>>>> |
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>>>>> Cheers! |
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>>>>> Meino |
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>>>>> |
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>>>>> |
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>>>> |
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>>>> cat /proc/cpu should give info for each thread. I've been running an i7 |
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>> 980 |
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>>>> Extreme processor @3.33GHz here at home for about 12 years or so. It's 6 |
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>>>> cores but shows 12 processors on both Gentoo and now Kubuntu. |
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>>>> |
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>>>> I generally run top and then hit '1' and 'z'. You can watch what |
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>> percentage |
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>>>> each core/thread is using. |
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>>>> |
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>>>> Time a BIG compile job twice, once with each kernel. If it's working |
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>> you'll |
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>>>> measure a significant difference in time. Note that it won't be 2x as |
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>>>> you'll also be limited by disk read/write throughput, but you'll know |
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>> it's |
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>>>> basically working. |
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>>>> |
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>>>> On Gentoo make sure you're compile settings in (I think make.conf - I no |
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>>>> longer run Gentoo much) are set to take advantage of all your cores and |
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>> not |
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>>>> limited to something smaller. Also watch overheating when using more |
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>>>> cores/threads. On older PCs like mine when you possibly have dust in CPU |
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>>>> coolers might not be as efficient as when they are new. |
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>>>> |
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>>>> HTH, |
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>>>> Mark |
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>>> |
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>>> Hi Mark, |
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>>> |
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>>> thank you for your explanations! :) |
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>>> |
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>>> /proc/cpu doesn't exist on my system....may be you are referring to |
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>>> /proc/cpuinfo? |
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>>> |
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>>> The problem was caused by a kernel misconfiguration by me. |
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>>> |
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>>> In the kernel setup there is a setting "Number of cores" which |
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>>> I had set to six ... since my CPU has 6 physical core. |
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>>> |
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>>> Setting this to twelve (and blurring the syntactically border between |
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>>> threads and cores thereby...) gives me twelves cores in top, htop |
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>>> and such and (as an example) compiling the kernel is faster - |
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>>> so it is not a display gimmick only. |
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>>> |
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>>> I think "Number of cores" is a misnomer...or am I wrong? |
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>>> |
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>>> Cheers! |
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>>> Meino |
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>>> |
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>> |
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>> Meino, |
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>> Yes, /proc/cpuinfo. Sorry. |
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>> |
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>> Well yes, I guess the 'Number of cores' is a misnomer if you're trying |
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>> to equate the language in the kernel against Intel/AMD marketing data for |
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>> physical cores. 6 physical cores with or without hyperthreading is still 6 |
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>> physical cores. However 6 physical cores (my processor) _WITH_ |
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>> hyperthreading enabled is 12 _LOGICAL_ cores which is more what I think the |
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>> kernel verbiage is about. Semantics I suppose. |
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>> |
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>> I'm glad you found it wasn't a gimmicky number. It really does work, |
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>> within the limits of the hardware being able to figure out what one thread |
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>> should be fetching or writing while the other thread is computing. It's not |
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>> a perfect 2:1 like 12 physical cores might be, but it's a lot less silicon |
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>> and therefore a lot less expensive. |
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>> |
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>> Cheers, |
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>> Mark |
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> |
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> Hi Mark, |
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> |
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> In the meanwhile I found "glance" and installed it, which is the |
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> bazooka-out-of-the-box-no-configuration terminal-brethren of "conky" |
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> :) |
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> |
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> Enough plugins enabled (which come with it preinstalled), you can |
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> watch in realtime, what each core/thread is doing right now...nearly. Big |
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> Brother for the sustem with no bad intention in mind. I am only |
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> curious :) |
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> |
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> And you get your sensors diplayed, the workload of your GPU (nvidia in |
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> my case), all processes and lot lot more. |
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> |
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> The faster the CPU gets (my previous PC was 12 years old...), the |
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> more the peripheral devices are becoming show stoppers ("stoppers" |
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> in the barest truth of its meaning). |
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> |
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> Unfortunatelu the SSD I ordered is in status "ready for delivery" |
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> since 23.03.2020....corona....you know... |
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> |
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> And with 12 cores enabled on a recent CPU and running for example a |
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> bigger update via emerge (enabled for 12 threads of course) |
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> ...all the cores are simply waiting a lot |
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> faster......for the harddisc :) |
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> |
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> Thanks for your help -- stay healthy! |
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> |
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> Cheers! |
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> Meino |
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|
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Meino, |
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|
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You might like the organization and details of |
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|
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"sys-process/htop" |
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|
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to look at cores and processes. |
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|
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|
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hth, |
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James |