Escala de tempo de alguma tarefa no kernel do linux?

Question

Estou estudando como o kernel do Linux funciona e me interessando pelo cronograma de qualquer coisa que aconteça no kernel.

Claro que sei que depende do HW, mas gostaria de obter um exemplo. Por exemplo,

• Rotina do serviço de interrupção: ~ 1 ms?
• Chamadas do sistema: ~ 10 ms?
• Printf (caractere de saída 1): 20ms? (não tenho certeza)

Seria bom se alguém pudesse deixar algum comentário ou recomendar um site que inclua informações como as acima.

    

Answer 1

Provavelmente você está procurando pelo topo .

A coluna

TIME + mostra o tempo de uso da CPU pelos processos.

top - 13:33:24 up 2 days, 21:28, 7 users,  load average: 0.27, 0.95, 0.92
Tasks: 733 total,  19 running, 691 sleeping,   0 stopped,  23 zombie
%Cpu(s): 18.4 us, 24.5 sy, 57.1 ni,  0.0 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st
KiB Mem:  16287248 total, 15047664 used,  1239584 free,   144600 buffers
KiB Swap: 37457960 total,  6876096 used, 30581864 free,  5184516 cached

  PID USER      PR  NI S  %CPU %MEM    TIME+  COMMAND
    1 root      20   0 S   0.0  0.0   1037:17 init
    2 root      20   0 S   0.0  0.0   0:00.03 kthreadd
    3 root      20   0 S   0.0  0.0  45:34.38 ksoftirqd/0
    5 root       0 -20 S   0.0  0.0   0:00.00 kworker/0:0H
    7 root       0 -20 S   0.0  0.0   0:00.00 kworker/u:0H
    8 root      rt   0 S   0.0  0.0   0:17.35 migration/0
    9 root      20   0 S   0.0  0.0   6:52.03 rcu_preempt
   10 root      20   0 S   0.0  0.0   0:00.00 rcu_bh
   11 root      20   0 S   0.0  0.0   0:00.00 rcu_sched
   12 root      rt   0 S   0.0  0.0   0:00.46 watchdog/0
   13 root      rt   0 S   0.0  0.0   0:00.47 watchdog/1
   14 root      20   0 S   8.4  0.0  22:22.00 ksoftirqd/1
   15 root      rt   0 S   0.0  0.0   0:19.23 migration/1
   18 root      rt   0 S   0.0  0.0   0:00.48 watchdog/2
   19 root      20   0 S   0.0  0.0  21:09.37 ksoftirqd/2
   20 root      rt   0 S   0.0  0.0   0:19.26 migration/2
   22 root       0 -20 S   0.0  0.0   0:00.00 kworker/2:0H
   23 root      rt   0 S   0.0  0.0   0:00.50 watchdog/3
   24 root      20   0 R   0.0  0.0  23:53.19 ksoftirqd/3
   25 root      rt   0 S   0.0  0.0   0:20.26 migration/3
   27 root       0 -20 S   0.0  0.0   0:00.00 kworker/3:0H
   28 root       0 -20 S   0.0  0.0   0:00.00 cpuset