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Old 04-11-2008, 08:23 AM
Qingqing Zhou
 
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Default Re: Re: Which qsort is used



On Sat, 17 Dec 2005, Dann Corbit wrote:

>
> The benchmarks say that they (order checks) are a good idea on average
> for ordered data, random data, and partly ordered data.
>


I interpret that in linux, 5000000 seems a divide for qsortpdq. Before
that number, it wins, after that, bsd wins more. On SunOS, qsortpdq takes
the lead till the last second -- I suspect this is due to the rand()
function:

Linux - #define RAND_MAX 2147483647
SunOS - #define RAND_MAX 32767

So in SunOS, the data actually not that scattered - so more favourate for
sorted() or reversed() check?

Regards,
Qingqing

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