Re: [BENCHMARK] nproc: netlink access to /proc information

[Paulo Marques]

Albert Cahalan wrote:
> ...
>
> This is crummy. It's done for wchan, since that is so horribly
> expensive, but I'm not liking the larger race condition window.
> Remember that PIDs get reused. There isn't a generation counter
> or UUID that can be checked.

I just wanted to call your attention to the kallsyms speedup patch that 
is now on the -mm tree.

It should improve wchan speed. My benchmarks for kallsyms_lookup (the 
function that was responsible for the wchan time) went from 1340us to 0.5us.

So maybe this is enough not to make wchan a special case anymore...

--
Paulo Marques - www.grupopie.com

To err is human, but to really foul things up requires a computer.
Farmers' Almanac, 1978
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/