full of process

  Hi,

  Sorry maybe for stupid q. I just some year of little exerpience with 
4.x & 5.x FreeBSD and don`t know even how to ask it to google... :)
I have current 5.3 FreeBSD updated etc.
Boot and have full in ps aux:
root       7  0.0  0.0     0   12  ??  SL    1:30PM   0:00.00 [acpi_task0]
root       8  0.0  0.0     0   12  ??  SL    1:30PM   0:00.00 [acpi_task1]
root       9  0.0  0.0     0   12  ??  SL    1:30PM   0:00.00 [acpi_task2]
root      10  0.0  0.0     0   12  ??  DL    1:30PM   0:00.00 [ktrace]
root      15  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq1: atkbd0]
root      16  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq3: sio1]
root      17  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq4: sio0]
root      18  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq5:]
root      19  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq6:]
root      20  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq7: ppc0]
root      21  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq8: rtc]
root      22  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq9: acpi0]
root      23  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq10:]
root      24  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq11:]
root      25  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq12:]
root      26  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq13:]
root      27  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq14: ata0]
root      28  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq15: ata1]
root      29  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq16:]
root      30  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq17:]
root      31  0.0  0.0     0   12  ??  WL    1:30PM   0:00.00 [irq18:]
....

I never see it before so I concern why so many irq something in process 
up...  PC is:
FreeBSD 5.3-RELEASE-p5 #0: Thu Feb 17 20:38:18 EET 2005
CPU: Intel(R) Xeon(TM) CPU 2.40GHz (2392.04-MHz 686-class CPU)
FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs
  cpu0 (BSP): APIC ID:  0
  cpu1 (AP): APIC ID:  1
  cpu2 (AP): APIC ID:  6
  cpu3 (AP): APIC ID:  7

Any point for understanding is it ok? :)

thanks to all,

Casper