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Re: Why not use GCC 3.0?

Falk Hueffner wrote:
> It depends on their amount. I'd estimate an unaligned trap takes about
> 100 cycles to handle. So if for example on my SX, I get 1000 unaligned
> traps per second, I loose about 0.1% of the performance. You can check
> the amount of unaligned traps by watching /proc/cpuinfo.

I have often seen these 'unaligned traps' lurking in my logs so I am curious about being able too see how many occur in cpuinfo and learning something
new about my Alpha. 
Looking at my cpuinfo I see....
	kernel unaligned acc	: 0 (pc=0,va=0)
	user unaligned acc	: 5407 (pc=120009bbc,va=1201c1abc)
	platform string		: Digital AlphaPC 164LX 533 MHz

Is "acc" short for access? I gather the unaligned trap is where the kernal detects and traps a memory access. Whats the number of unaligned traps, the
zero number in kernal unaligned acc or the 5407? I presume that my cpuinfo is telling me that whatever causes these unaligned traps is something that
runs from user space?

Michael Lake
Active caver, Linux enthusiast and interested in anything technical.
Safety Convenor, Australian Speleological Federation
Owner, Speleonics (Australia)

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