[erlang-questions] clueless performance question

Per Hedeland <>
Sat Jun 14 12:21:57 CEST 2008


Kevin Scaldeferri <> wrote:
>
>On Jun 11, 2008, at 9:21 AM, Hynek Vychodil wrote:
>
>> What I can write about WF1 is, this was a little bit ... well I  
>> write it clearly: "stupid" because WF1 was measured with data file  
>> cached. It is why this Perl implementation won. This implementation  
>> mmap file and than forked processes around this file and then rush.  
>> Each process reads it's mmap forked copy which in normal cause  
>> random access to disk and must end with far slowest solution.
>>
>>
>
>I don't think it can really be considered cheating to take advantage  
>of features provided by the OS.

Hm, I think you misunderstand - it's not the mmap that is cheating, it's
the caching. Or do you know of an OS that has the feature of always
keeping all files cached in memory? (Let me know so I can avoid it.:-)

--Per Hedeland



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