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Re: Parallelhashlist was updated to version 1.41 ...

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I write:
>But the scalability of parallelhashlist does depend on the data keys that 
>are presented to parallelhashlist, when the data keys are hashed and are 
>very well distributed across the segments, in fact you can get a perfect 4X 
>scaling both on reads and writes.


I mean a perfect scaling on 4 cores...



Regards,

Amine Moulay Ramdane.


"aminer" <aminer@videotron.ca> wrote in message 
news:jqe5ga$ts$1@dont-email.me...
> Hello,
>
>
> I have done those tests to show some numbers...
>
> But the scalability of parallelhashlist does depend on the data keys
> that are presented to parallelhashlist, when the data keys are hashed
> and are very well distributed across the segments, in fact you can
> get a perfect 4X scaling both on reads and writes.
>
>
>
> Thank you.
>
> Amine Moulay Ramdane.
>
>
> "aminer" <aminer@videotron.ca> wrote in message 
> news:jqe4lc$sf9$1@dont-email.me...
>>
>>
>> Hello,
>>
>>
>> I have done some scalability tests on parallelhashlist 1.41
>> on an Intel Core 2 Quad Q6600..
>>
>> Using 4 threads on 4 cores using the find()  method i had a perfect scale 
>> of 4X .
>>
>> Using 4 threads on 4 cores using the Add()  method i scaled 3.4X
>>
>>
>>
>> Regards,
>> Amine Moulay Ramdane.
>>
>>
>>
>> .
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> "aminer" <aminer@videotron.ca> wrote in message 
>> news:jq67al$4i9$1@dont-email.me...
>>>
>>> Hello all,
>>>
>>>
>>> I have updated parallelhashlist to version 1.41..
>>>
>>>
>>> I have modified parallelhashlist to use 128 locks, but you
>>> have to use a hashsize in power of 2 and greater to 1000,
>>> how do you pass a hashsize in power of 2  to the constructor?
>>> by using shl operation like this
>>>
>>>
>>> trait:=TCaseinsensitiveTraits.create;;
>>> hash1:=TParallelHashList.create(trait,1 shl 25);
>>>
>>>
>>> Why do you have to use a power of 2 ?
>>>
>>>
>>> Please read this:
>>>
>>>
>>> Power-of-Two Hash Table Size
>>>
>>>
>>> "Any data structures 101 book will say choose a prime for the
>>> number of buckets, so that the bucket's index can easily be computed
>>> by h(k) = k mod m, where k is the key value and m is the bucket size.
>>> While this approach is straight-forward, there are a number of issues
>>> with it, including slow modulo performance. ConcurrentHashMap instead
>>> uses a power-of-two rule"
>>>
>>> http://work.tinou.com/2008/09/performance-optimization-in-concurrenthashmap.html
>>>
>>>
>>>
>>> I am using modulo functions inside parallelhashlist, and using a number 
>>> of locks
>>> in power of 2, so you have to use hashsize in power of 2 ,  this will 
>>> make the
>>> modulo function of the delphi and freepascal compilers 10X faster.
>>>
>>>
>>> You can download parallelhashlist version 1.41 from:
>>>
>>> http://pages.videotron.com/aminer/
>>>
>>>
>>>
>>>
>>> Thank you.
>>>
>>> Amine Moulay Ramdane.
>>>
>>>
>>>
>>>
>>
>>
>
> 

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Thread

Parallelhashlist was updated to version 1.41 ... "aminer" <aminer@videotron.ca> - 2012-05-30 18:34 -0500
  Re: Parallelhashlist was updated to version 1.41 ... "aminer" <aminer@videotron.ca> - 2012-05-30 18:38 -0500
  Re: Parallelhashlist was updated to version 1.41 ... "aminer" <aminer@videotron.ca> - 2012-05-30 18:46 -0500
  Re: Parallelhashlist was updated to version 1.41 ... "aminer" <aminer@videotron.ca> - 2012-06-02 18:38 -0500
    Re: Parallelhashlist was updated to version 1.41 ... "aminer" <aminer@videotron.ca> - 2012-06-02 18:52 -0500
      Re: Parallelhashlist was updated to version 1.41 ... "aminer" <aminer@videotron.ca> - 2012-06-02 18:56 -0500
  Re: Parallelhashlist was updated to version 1.41 ... "aminer" <aminer@videotron.ca> - 2012-06-02 18:40 -0500

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