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Threadpool engien and scalability [1]

Cross-posted to 2 groups.

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Hello,

I have corrected my mistakes , please read again:

If you take a look at my threadpool engine:

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

you will notice that it does not scale in the execute() method
cause LockedIncLong(balance1) is expensive.

here is the execute method:

==

function TThreadPool.execute(func:TMyProc;const Context: Pointer): Boolean;

var
local_balance,local_count:long;

params: PParams;
p:pointer;

begin
new(params);
setlength(params^,1);
params^[0].proc:=func;
params^[0].data:=context;

local_balance:=LockedIncLong(balance1) mod FThreadCount;
while not Queues[local_balance].push(tobject(params)) do sleep(0);
events[local_balance].setevent;
end;

===

Now to be able to scale the execute() method we have to add a new
execute1() method that will be called from mutiple threads, i have to
use LockedIncLong() but it will be called only once:

==

function TThreadPool.execute1(func:TMyProc;const Context:
Pointer;index:long): Boolean;

params: PParams;
p:pointer;

begin
new(params);
setlength(params^,1);
params^[0].proc:=func;
params^[0].data:=context;

if index = 0
then
begin
index:=LockedIncLong(balance1) mod FThreadCount;
end;

while not Queues[index].push(tobject(params)) do sleep(0);
events[index].setevent;
end;

=


so we have to call the execute1() method from mutiple threads like this:

and we have to initialize index to zero before:, like this:

ThreadPool.execute1(myproc,data,index)

I am using mutiple lockfree FIFO queues inside my threadpool engine,
so that there is less contention and using work-stealing also, so after
adding execute1() methods , this threadpool engine will become scalable.
this threadpool engine can also be used as a scalable queue
(not a strict FIFO queue, but it's also useful).

This threadpool engine is useful and that is what's important.



I will try to update my threadpol engine soon.



Thank you,
Amine Moulay Ramdane.

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Thread

Threadpool engien and scalability [1] "aminer" <aminer@videotron.ca> - 2012-10-01 12:59 -0500
  Re: Threadpool engien and scalability [1] "aminer" <aminer@videotron.ca> - 2012-10-01 13:34 -0500
  Re: Threadpool engien and scalability [1] "aminer" <aminer@videotron.ca> - 2012-10-01 13:48 -0500
  Re: Threadpool engien and scalability [1] "aminer" <aminer@videotron.ca> - 2012-10-01 14:02 -0500

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