.\" Hey Emacs! This file is -*- nroff -*- source. .\" .\" This manpage is Copyright (C) 2003 Matthew Wilcox .\" .\" Permission is granted to make and distribute verbatim copies of this .\" manual provided the copyright notice and this permission notice are .\" preserved on all copies. .\" .\" Permission is granted to copy and distribute modified versions of this .\" manual under the conditions for verbatim copying, provided that the .\" entire resulting derived work is distributed under the terms of a .\" permission notice identical to this one. .\" .\" Since the Linux kernel is constantly changing, this manual page may .\" be incorrect or out-of-date. The author(s) assume no responsibility .\" for errors or omissions, or for damages resulting from the use of the .\" information contained herein. .\" .\" Formatted or processed versions of this manual, if unaccompanied by .\" the source, must acknowledge the copyright and authors of this work. .\" .TH KSOFTIRQD 9 2003-08-24 "Linux 2.6.0" "Linux Programmer's Manual" .SH NAME ksoftirqd \- Softirq daemon .SH DESCRIPTION .B ksoftirqd is a per-cpu kernel thread that runs when the machine is under heavy soft-interrupt load. Soft interrupts are normally serviced on return from a hard interrupt, but it's possible for soft interrupts to be triggered more quickly than they can be serviced. If a soft interrupt is triggered for a second time while soft interrupts are being handled, the .B ksoftirq daemon is triggered to handle the soft interrupts in process context. If .B ksoftirqd is taking more than a tiny percentage of CPU time, this indicates the machine is under heavy soft interrupt load. .SH HISTORY .B ksoftirqd was introduced during the 2.3 development series as part of the softnet work by Alexey Kuznetsov and David Miller.