On 04/09/2018 10:43 AM, Ken Moffat wrote:

I meant the bit underneath that - I only have 4 cores (8 on my
haswell) and I use 40 line terms so lots of room for details, here's
a quick copy of the first few processes on an idle desktop:

   PID USER      PR  NI    VIRT    RES  %CPU %MEM     TIME+ S COMMAND
  1321 root      20   0  370.6m  55.4m   1.3  0.7   0:35.85 S Xorg
22670 ken       20   0 3199.1m 146.4m   0.7  1.8   0:06.61 S falkon
22733 ken       20   0 2276.9m 348.6m   0.7  4.4   0:21.15 S QtWebEngineProc
     1 root      20   0    4.2m   1.4m   0.0  0.0   0:00.40 S init

At that moment Xorg was using most cpu (1.3%).

You got me interested. Evidently a process can use multiple cores when doing threading. A separate process is created with fork(), but not with threads ( pthread_create() ). So depending on the number of threads, a single process can use multiple cpus (cores) and top will show that as a process with %CPU > 100.

https://stackoverflow.com/questions/807506/threads-vs-processes-in-linux?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa

  -- Bruce

--
http://lists.linuxfromscratch.org/listinfo/blfs-support
FAQ: http://www.linuxfromscratch.org/blfs/faq.html
Unsubscribe: See the above information page

Reply via email to