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==2010 ...==
 
==2010 ...==
 
* [http://www.talkchess.com/forum/viewtopic.php?t=33705 Stockfish-1.7.0 Hyper-threading Detection] by [[Louis Zulli]], [[CCC]], April 09, 2010
 
* [http://www.talkchess.com/forum/viewtopic.php?t=33705 Stockfish-1.7.0 Hyper-threading Detection] by [[Louis Zulli]], [[CCC]], April 09, 2010
 +
* [http://www.talkchess.com/forum/viewtopic.php?t=36103 Hyperthreading] by [[Gerd Isenberg]], [[CCC]], September 17, 2010
 
* [http://www.talkchess.com/forum/viewtopic.php?t=36465 To hyperthread or not to hyperthread (Crafty tested)] by [[Martin Thoresen]], [[CCC]], October 24, 2010 » [[Crafty]]
 
* [http://www.talkchess.com/forum/viewtopic.php?t=36465 To hyperthread or not to hyperthread (Crafty tested)] by [[Martin Thoresen]], [[CCC]], October 24, 2010 » [[Crafty]]
* [http://www.talkchess.com/forum/viewtopic.php?t=36103 Hyperthreading] by [[Gerd Isenberg]], [[CCC]], September 17, 2010
+
* [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=36637 Input / ThinkingThreads] by [[Richard Allbert]], [[CCC]], November 08, 2010
 
* [http://www.talkchess.com/forum/viewtopic.php?t=36966 Thread management / organization in parallel processing?] by [[Pham Hong Nguyen|Nguyen Pham]], [[CCC]], December 06, 2010
 
* [http://www.talkchess.com/forum/viewtopic.php?t=36966 Thread management / organization in parallel processing?] by [[Pham Hong Nguyen|Nguyen Pham]], [[CCC]], December 06, 2010
 
'''2011'''
 
'''2011'''
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* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=31863 Hyperthreading debate reopened?] by Zat, [[Computer Chess Forums|Rybka Forum]], December 03, 2016
 
* [http://rybkaforum.net/cgi-bin/rybkaforum/topic_show.pl?tid=31863 Hyperthreading debate reopened?] by Zat, [[Computer Chess Forums|Rybka Forum]], December 03, 2016
 
* [http://www.talkchess.com/forum/viewtopic.php?t=62622 Diminishing returns and hyperthreading] by [[Kai Laskos]], [[CCC]], December 27, 2016 » [[Depth#DiminishingReturns|Diminishing Returns]], [[Match Statistics]], [[Playing Strength]]
 
* [http://www.talkchess.com/forum/viewtopic.php?t=62622 Diminishing returns and hyperthreading] by [[Kai Laskos]], [[CCC]], December 27, 2016 » [[Depth#DiminishingReturns|Diminishing Returns]], [[Match Statistics]], [[Playing Strength]]
'''2017 ...'''
+
'''2017'''
 
* [http://www.talkchess.com/forum/viewtopic.php?t=64441 Core behaviour] by [[Ed Schroder]], [[CCC]], June 28, 2017 » [[Engine Testing]]
 
* [http://www.talkchess.com/forum/viewtopic.php?t=64441 Core behaviour] by [[Ed Schroder]], [[CCC]], June 28, 2017 » [[Engine Testing]]
 
* [http://www.talkchess.com/forum/viewtopic.php?t=65844 Lazy SMP >4 Thread Slowdown] by [[Can Cetin]], [[CCC]], November 29, 2017 » [[Lazy SMP]]
 
* [http://www.talkchess.com/forum/viewtopic.php?t=65844 Lazy SMP >4 Thread Slowdown] by [[Can Cetin]], [[CCC]], November 29, 2017 » [[Lazy SMP]]
 
: [http://www.talkchess.com/forum/viewtopic.php?t=65844&start=4 Re: Lazy SMP >4 Thread Slowdown] by [[Ronald de Man]], [[CCC]], November 29, 2017
 
: [http://www.talkchess.com/forum/viewtopic.php?t=65844&start=4 Re: Lazy SMP >4 Thread Slowdown] by [[Ronald de Man]], [[CCC]], November 29, 2017
 +
'''2018'''
 
* [http://www.talkchess.com/forum/viewtopic.php?t=67186 More questions about threads] by [[Patrice Duhamel]], [[CCC]], April 21, 2018 » [[Young Brothers Wait Concept]]  
 
* [http://www.talkchess.com/forum/viewtopic.php?t=67186 More questions about threads] by [[Patrice Duhamel]], [[CCC]], April 21, 2018 » [[Young Brothers Wait Concept]]  
 +
'''2019'''
 
* [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=69658 Hyperthreading on or off] by lovetb, [[CCC]], January 20, 2019
 
* [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=69658 Hyperthreading on or off] by lovetb, [[CCC]], January 20, 2019
 
: [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=69658&start=5 Re: Hyperthreading on or off] by [[Andrew Grant]], [[CCC]], January 20, 2019
 
: [http://www.talkchess.com/forum3/viewtopic.php?f=2&t=69658&start=5 Re: Hyperthreading on or off] by [[Andrew Grant]], [[CCC]], January 20, 2019
 +
* [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=70586 Prefetch and Threading] by [[Dennis Sceviour]], [[CCC]], April 25, 2019 » [[Memory]], [[Transposition Table]]
 +
* [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=70919 strategies for finding slowdows in lazy smp] by [[Folkert van Heusden]], [[CCC]], June 04, 2019 » [[Lazy SMP]], [[Nodes per Second]]
 +
* [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=71739 Multithreaded noob question] by [[Michael Sherwin]], [[CCC]], September 06, 2019
  
 
=External Links=  
 
=External Links=  

Latest revision as of 21:11, 13 December 2019

Home * Programming * Thread

Two threads on a single processor [1]

A Thread is the smallest unit of processing that can be scheduled by an operating system. One or multiple threads can exist within the same process to share its resources such as memory. Modern operating systems support both time-sliced and multiprocessor threading within a process scheduler. Some operating systems such as Windows distinguish worker threads from GUI-threads, which incorporate a message loop, able to receive messages from worker threads. Threads share global data of the process, but use disjoint stacks for local variables.

Chess programs using threads for a parallel search have to deal with synchronization issues, if multiple threads read and write none atomic global data simultaneously, requiring multiple read and/or write cycles. A good step to make a program thread safe, is to avoid global variables and to keep board and game states as locals on the stack. To minimize context switching, chess programs often implement a thread pooling pattern along with explicitly or implicitly controlling processor affinity, where the number of threads of the chess program is less or equal to the number of physical processor cores. Threads are further versatile to control standard input inside an engine.

See also

Publications

1994 ...

2000 ...

2010 ...

Forum Posts

1999

2000 ...

2005 ...

2010 ...

2011

2012

2013

2014

2015 ...

Explanation for non-expert? by Louis Zulli, CCC, February 16, 2015 » Stockfish

2016

Re: Baffling multithreading scaling behavior by Robert Hyatt, CCC, September 07, 2016

2017

Re: Lazy SMP >4 Thread Slowdown by Ronald de Man, CCC, November 29, 2017

2018

2019

Re: Hyperthreading on or off by Andrew Grant, CCC, January 20, 2019

External Links

Thread

Multithreading

Posix

Windows

Creating Threads

C++

Java

GPU

References

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