Re: x86: 4kstacks default

From: Andi Kleen
Date: Sun Apr 20 2008 - 17:41:18 EST


Daniel Hazelton wrote:

> At 12 threads per request it'd only take about 4200 outstanding requests. That
> is high, but I can see it happening.

If it happens it just won't work on 32bit.

> Just makes you sound foolish. Run the numbers yourself and you'll see that it
> is easy for a machine running highly threaded code to easily hit 50K threads.

I ran the numbers and the numbers showed that you need > 1.5GB of lowmem
with a somewhat realistic scenario (32K per thread) at 50k threads. And
subtracting 4k from that 32k number won't make any significant
difference (still 1.3GB)

If you claim that works on a 32bit system with typically 300-600MB
lowmem available (which is also shared by other subsystem) I know who
sounds foolish.

-Andi
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