On Mon, 26 Nov 2007 22:36:17 -0600 Robert Hancock <[EMAIL PROTECTED]> wrote:
> [EMAIL PROTECTED] wrote: > > Question: Why is ksoftirqd eating about 5 to 10 percent of my CPU > > on an idle system? The problem occurs if I config the kernel with > > tickless support (i.e. CONFIG_TICK_ONESHOT=y). (Thanks to > > "oprofile" for putting me onto this.) > > > > I have noted this same problem on kernel versions: 2.6.23.1, > > 2.6.23.8 and 2.6.23.9 > > > > ************************************************************************** > > *** Output from "vmstat -n 1 10" -- Note very high context switch > > rate *** *** This is on a idle > > machine! *** > > ************************************************************************** > > > > procs -----------memory---------- ---swap-- -----io---- --system-- > > ----cpu---- > > r b swpd free buff cache si so bi bo in cs > > us sy id wa > > 0 0 0 1925556 4768 116104 0 0 124 2 6 > > 7538 1 2 96 1 > > 0 0 0 1925556 4768 116104 0 0 0 0 2 > > 147329 0 1 99 0 > > What did oprofile show? It should be able to narrow down what > function(s) are responsible for the CPU usage.. > or better, what does powertop version 1.9 show? that tends to show tickless wakeup artifacts quite nicely -- If you want to reach me at my work email, use [EMAIL PROTECTED] For development, discussion and tips for power savings, visit http://www.lesswatts.org - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
