lkml.org 
[lkml]   [2006]   [Jul]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 10/17] 2.6.17.1 perfmon2 patch for review: PMU context switch
In-Reply-To: <20060704152857.GA6999@frankl.hpl.hp.com>

On Tue, 4 Jul 2006 08:28:57 -0700, Stephan Eranian wrote:

> Here is what I get on my dual 2.4GHz Opteron 250:
>
> booted with idle=halt
> $ pfmon --us-c -ecpu_clk_unhalted,interrupts_masked_cycles_with_interrupt_pending,interrupts_masked_cycles,cycles_no_fpu_ops_retired -k --system-wide -t 10
> <session to end in 10 seconds>
> CPU0 11,356,210 CPU_CLK_UNHALTED
> CPU0 0 INTERRUPTS_MASKED_CYCLES_WITH_INTERRUPT_PENDING
> CPU0 3,836,107 INTERRUPTS_MASKED_CYCLES
> CPU0 23,910,784,532 CYCLES_NO_FPU_OPS_RETIRED
> CPU1 19,303,632 CPU_CLK_UNHALTED
> CPU1 0 INTERRUPTS_MASKED_CYCLES_WITH_INTERRUPT_PENDING
> CPU1 13,942,265 INTERRUPTS_MASKED_CYCLES
> CPU1 23,911,872,654 CYCLES_NO_FPU_OPS_RETIRED

So it looks like your Opteron continues to count CYCLES_NO_FPU_OPS_RETIRED
at full clock speed even when halted.

My Turion appears to slow down to ~40 MHz when halted and counts those
events at that speed. Using idle=poll shows no slowdown, as expected,
and unhalted clocks equals cycles_no_fpu_ops_retired.

--
Chuck
"You can't read a newspaper if you can't read." --George W. Bush
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-07-06 19:43    [W:0.029 / U:0.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site