F**e
发帖数: 593 | 1 Say if I want to find the actual time of 100 jiffies on my linux,
how do I do it?
Thanks a lot! |
c********e
发帖数: 417 | 2 As I read it, jiffies are the number of elapsed ticks starting from
the system start. It's increment by 1 for every timer interrupt.
So that depends on how linux programs the programmable timer.
Normally, it's 10ms per tick.
【在 F**e 的大作中提到】
: Say if I want to find the actual time of 100 jiffies on my linux,
: how do I do it?
: Thanks a lot!
|
m*****e
发帖数: 4193 | 3
In user space it's ALWAYS 100 jiffies per second (at least on x86).
In kernel space it depends. Recent kernels have changed it internally.
【在 c********e 的大作中提到】
: As I read it, jiffies are the number of elapsed ticks starting from
: the system start. It's increment by 1 for every timer interrupt.
: So that depends on how linux programs the programmable timer.
: Normally, it's 10ms per tick.
|
F**e
发帖数: 593 | 4 Thank you, microbe and clarkmouse!
Actually my problem was: I was getting process info from
/proc//stat
One of the properties I am interested in is the usertime(utime) there. The man
says utime is "The number of jiffies that this process has been scheduled in
user mode".
So that means the number I get there divided by 100 will give me the number of
seconds? Right? Just want to make sure. Thanks.
【在 m*****e 的大作中提到】
:
: In user space it's ALWAYS 100 jiffies per second (at least on x86).
: In kernel space it depends. Recent kernels have changed it internally.
|
