Timing Facilities

2 messages, 2 authors, 2001-02-22 · open the first message on its own page

Timing Facilities

From: Steve Poole <hidden>
Date: 2001-02-22 05:24:57

I have written a small assembly fragment to read the TB register that runs
under Linux (YDL/BLL). What is the definition of a "tick" or "jiffie" under
Linux. When some code is run under MacOS (400MHz G4) the results are
*faster* (the numbers returned are lower) than when I run on a 500MHz G4. I
appreciate any input.

Steve...
Steve Poole
IS2 / PeerTechnologies
Phone 713.806.0329
eFax   240.539.7413


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Re: Timing Facilities

From: Joseph P. Garcia <hidden>
Date: 2001-02-22 06:10:16

On Wed, 21 Feb 2001 23:24:57 -0600, Steve Poole [off-list ref] wrote:
I have written a small assembly fragment to read the TB register that runs
under Linux (YDL/BLL). What is the definition of a "tick" or "jiffie" under
Linux. When some code is run under MacOS (400MHz G4) the results are
*faster* (the numbers returned are lower) than when I run on a 500MHz G4. I
appreciate any input.
I beleive there are 1*HZ jiffies in one second.  Used in the kernel's timer_list struct (to name one use), which basically has the kernel run a function at a specific time.  ex, setting the 'expires' value to (jiffies + HZ) will cause it to run one second from now.

--
Joseph P. Garcia
http://www.execpc.com/~jpgarcia

** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/
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