Re: pi_test predicted results

From: Esben Nielsen
Date: Wed Jun 01 2005 - 13:08:52 EST


The documentation is wrong... To my defence, I belived that was the result
when I wrote it because I assumed a slightly different behaviour, which
you can only obtain on UP.

Anyways, I think we found that the general bound is

2^{depth} ms

(I have to find the old mails to check it though...)

It does require many threads though. But N=10 for d=3 giving 8 ms of
maximum latency should be enough. Notice, that the worst case should be
hit very rarely.

Esben


On Wed, 1 Jun 2005, Daniel Walker wrote:

>
> What would you predict the results of the pi test with --tasks 10
> and --depth 3 ?
>
> From the docmentation it looks like depth N adds N milliseconds to
> the locking latency . It seems like increasing the numbers of tasks would
> also increase the locking latency by M tasks == M milliseconds. But I
> thought I would ask to be sure..
>
> Daniel
>
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