man9/ksoftirqd.9

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  22 .TH KSOFTIRQD 9 2003-08-24 "Linux 2.6.0" "Linux Programmer's Manual"
  23 .SH NAME
  24 ksoftirqd \- Softirq daemon
  25 .SH DESCRIPTION
  26 .B ksoftirqd
  27 is a per-cpu kernel thread that runs when the machine is under heavy
  28 soft-interrupt load.  Soft interrupts are normally serviced on return from
  29 a hard interrupt, but it's possible for soft interrupts to be triggered
  30 more quickly than they can be serviced.  If a soft interrupt is triggered
  31 for a second time while soft interrupts are being handled, the
  32 .B ksoftirq
  33 daemon is triggered to handle the soft interrupts in process context.
  34 If
  35 .B ksoftirqd
  36 is taking more than a tiny percentage of CPU time, this indicates the
  37 machine is under heavy soft interrupt load.
  38 .SH HISTORY
  39 .B ksoftirqd
  40 was introduced during the 2.3 development series as part of the
  41 softnet work by Alexey Kuznetsov and David Miller.