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