On Sun, May 15, 2011 at 01:48:43PM -0400, Robert P. J. Day wrote:
On Sun, 15 May 2011, Greg KH wrote:
On Sun, May 15, 2011 at 12:41:30PM -0400, Robert P. J. Day wrote:
given that ubuntu ships with the kernel configured for tickless behaviour, and that RHEL6 also ships tickless, is it safe to say that tickless is now the standard configuration? is there a compelling reason to *not* run tickless with the latest 2.6 kernels?
Yes it is the "standard" and no, there is not any reason to not enable it. Unless you like burning extra power for no reason.
ok, good to know. i assume, then, that it's fairly pointless to use the value of "jiffies" for anything that requires even moderate accuracy. i was poking around the timer code, and i can see this in kernel/time/timekeeping.c:
No, never access jiffies directly, use the correct delay and timer functions instead, they will handle things properly. And that's the way to get correct accuracy if you need it. thanks, greg k-h