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Re: ParallelHashList was updated to version 1.3 ...

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Hello again,

One final touch to parallelhashlist: i have just added this
to the constructor:

if AHashSize < 1000
then
begin
 writeln('Constructor''s Hash size argument must be superior or equal to 
1000');
 exit;
end;



So as you have noticed the hash size argument must be superior or equal to 
1000


Please download again the parallelhashlist zipfile from:

http://pages.videotron.com/aminer/



Amine Moulay Ramdane.




"aminer" <aminer@videotron.ca> wrote in message 
news:jp3qm5$hb0$1@dont-email.me...
>
> Hello,
>
>
> In my previous version of ParallelHashList even if i have used
> lock striping for the hash chains, synchronizing access to the counter
> that computes the number of entries in the hashmap was reintroducing
> the scalability problem of exclusive locking, this counter was  called
> a hot field because every mutative operation needs to access it.
> In this new version 1.3 of parallelhashlist i have splited the global
> counter to many counters to enhance the scalability... also i have 
> changed
> parallelhashlist to use only 100 lightweight  MREWs 
> (multiple-readers -exclusive-writer)
> this will lower the memory consumption  and this will allow to parallelize
> the writes and reads in separate chains , and also to parallelize the 
> reads
> in the same chain of the hashmap , so this will give a good performance
> and a good scalability .
>
> Description:
>
> A Parallel HashList with O(1) (best case) and O(log(n)(worst case)
> access that use a hash based method that uses lock striping and
> 100 lightweight  MREWs (multiple-readers -exclusive-writer).
> This will allow to parallelize the writes and reads in separate chains , 
> and
> also to parallelize the reads in the same chain.
>
>
> You can download parallelhashlist from:
>
> http://pages.videotron.com/aminer/
>
>
> Language: FPC Pascal v2.2.0+ / Delphi 5+: http://www.freepascal.org/
>
>
> Operating Systems: Win , Linux and Mac (x86).
>
> and please take a look at the benchmarks here:
>
> http://pages.videotron.com/aminer/parallelhashlist/queue.htm
>
> Note: When i have done those benchmarks , there was not enough/much items
> organized as a self-balancing tree in the individual chains of the 
> hashtable, so ,
> almost all the items was found and inserted in O(1) , so the parallel part 
> in the
> Amdahl equation was not much bigger compared to to the serial part. But 
> you
> will notice in pratice that as soon as you will have more items on the 
> chains of
> the Hashtable, organized as self-balancing tree, with a worst case log(n) 
> , the
> parallel part will become bigger in the Amdahl equation and you will have 
> better
> performance and scalability than the numbers in the graph of the 
> benchmarks ...
>
>
>
> Thank you.
>
> Amine Moulay Ramdane.
>
>
>
> 

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Thread

ParallelHashList was updated to version 1.3 ... "aminer" <aminer@videotron.ca> - 2012-05-17 17:30 -0500
  Re: ParallelHashList was updated to version 1.3 ... "aminer" <aminer@videotron.ca> - 2012-05-17 18:00 -0500
    Re: ParallelHashList was updated to version 1.3 ... "aminer" <aminer@videotron.ca> - 2012-05-17 18:28 -0500
    Re: ParallelHashList was updated to version 1.3 ... "aminer" <aminer@videotron.ca> - 2012-05-17 19:17 -0500
  Re: ParallelHashList was updated to version 1.3 ... "aminer" <aminer@videotron.ca> - 2012-05-17 19:21 -0500
  Re: ParallelHashList was updated to version 1.3 ... "aminer" <aminer@videotron.ca> - 2012-05-17 19:58 -0500
    Re: ParallelHashList was updated to version 1.3 ... "aminer" <aminer@videotron.ca> - 2012-05-17 20:02 -0500
  Re: ParallelHashList was updated to version 1.3 ... "aminer" <aminer@videotron.ca> - 2012-05-17 21:01 -0500
  Re: ParallelHashList was updated to version 1.3 ... "aminer" <aminer@videotron.ca> - 2012-05-17 21:23 -0500

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