Can jiffies freeze?

Mulyadi Santosa mulyadi.santosa at
Tue Jan 22 03:27:06 EST 2013


On Tue, Jan 22, 2013 at 12:51 PM, sandeep kumar
<coolsandyforyou at> wrote:
> Hi all
> As far as I know jiffie counter is incremented HZ times/second. And it is
> used to measure the time lapses in the kernel code.
> I m seeing a case where, actualy time spent in some module using giffies is
> zero,

theoritically possible, especially under NO_HZ a.k.a dynamic tick, but
mind you 2 secs is so long, so maybe something is not right.

BTW, like Anish says, how do you read it? It sounds like you read
cached value of jiffies...but that's just my guess...


Mulyadi Santosa
Freelance Linux trainer and consultant


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