Heterogeneous Hierarchical Asynchronous Tasking - Revision history

imported>Wpinfold: Replaced content with "Content moved to https://wiki.modelado.org/Hierarchical_Heterogeneous_Asynchronous_Tasking here please delete this page from your bookmarks."

2017-02-02T06:48:55Z

Replaced content with "Content moved to https://wiki.modelado.org/Hierarchical_Heterogeneous_Asynchronous_Tasking here please delete this page from your bookmarks."

← Older revision		Revision as of 06:48, February 2, 2017
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	~~Welcome~~ to ~~the wiki pages for the Hierarchical Heterogeneous Asynchronous Tasking (HiHAT, pronounced high-hat, like the musical instrument) effort.~~		Content moved to [[https://wiki.modelado.org/Hierarchical_Heterogeneous_Asynchronous_Tasking here]] please delete this page from your bookmarks.

	~~We are currently in the first phase of the development of this framework, in which we are~~
	* Revealing a striking commonality of interests
	* Building momentum toward a production-quality, retargetable framework for broad community use
	* Gathering usage models and requirements in the form of user stories with acceptance criteria
	* Identifying representative and influential applications that serve as poster children for HiHAT, and developers who are ready to invest in good software engineering to produce an effective, durable, scalable and retargetable result

	~~Sign up at the~~ [[https://~~www~~.~~eventbrite~~.~~com~~/~~e/heterogeneous-hierarchical-asynchronous-tasking-hhat-startup-tickets-30237046821\|Eventbrite site]] to get an invite to regular meetings, whose MINUTES are kept [[HHAT Usage Meeting Minutes\|HERE]].~~

	~~This wiki presently serves to inform the development of a HiHAT framework in four ways:~~
	~~# [[Glossary and References]]~~
	~~# [[Usage models]]~~
	~~#* prosaic descriptions of how HiHAT would be used~~
	~~#* Examples: static vs. dynamic, C++ features, task graph vs. imperative interfaces, multiple files vs. one source file~~
	~~#* purpose: get a deeper appreciation of new usages, see commonalities and patterns across multiple usages~~
	~~# [[User stories~~]]
	~~#* formulaic, succinct and more rigorous descriptions of what is wanted out of HHAT~~
	~~#* As a <role>, I want <function> so that <benefit>, such that <acceptance criteria>~~
	~~#* purpose: get more rigorous about what is needed~~
	~~# [[Applications]]~~
	~~#* Brief description of app and its business importance~~
	~~#* Brief description of app domain~~
	~~#* Qualitative or quantitative analysis of where and how it would benefit from HHAT~~
	~~#* Expected time table for delivery of a solution (e.g. readiness for the arrival of a new supercomputer at a USG lab), and resources available to implement it with HHAT~~
	~~#* purpose: identify apps that could lead vehicles that drive the development of an open source project and that would be a poster child that would build confidence for others to follow~~

	~~Some key points about~~ this ~~wiki and what gets posted here~~
	* All contributions of ideas and code examples here are considered public. There are no implied restrictions on the reuse of intellectual property or code, in open source or proprietary contexts.
	* This is a community effort. It is expected that the whole community will benefit from ~~the considerable efforts of many generous and conscientious people who are working for the common good. Thanks for~~ your ~~investment!~~

	At this point, HiHAT is a descriptive handle, rather than a proper name. It does suggest a top-down and bottom-up approach. Being able to wear many hats is suggestive of the many user-facing interfaces.

	For a HiHAT framework to be viable, it needs to support several targets, provide common building blocks, services and transformations in an open architecture, and enable a variety of different applications and frameworks to be built on top. The diagram below suggests one possible arrangement.

	~~[[File:HHAT_Diagram.jpg\|center\|600px\|caption="Possible HiHAT architecture"]]~~

	~~If the middle layers are modular, implementations can be created, plugged in, and iteratively refined. They may be freely shared or premium versions could be offered commercially~~.

imported>Cnewburn at 13:56, February 1, 2017

2017-02-01T13:56:25Z

← Older revision		Revision as of 13:56, February 1, 2017
Line 1:		Line 1:
	Welcome to the wiki pages for the Hierarchical Heterogeneous Asynchronous Tasking (HiHAT) effort.		Welcome to the wiki pages for the Hierarchical Heterogeneous Asynchronous Tasking (HiHAT, pronounced high-hat, like the musical instrument) effort.

	We are currently in the first phase of the development of this framework, in which we are		We are currently in the first phase of the development of this framework, in which we are

imported>Cnewburn at 04:02, February 1, 2017

2017-02-01T04:02:45Z

← Older revision		Revision as of 04:02, February 1, 2017
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	Welcome to the wiki pages for the Heterogeneous ~~Hierarchical~~ Asynchronous Tasking (~~HHAT~~) effort.		Welcome to the wiki pages for the Hierarchical Heterogeneous Asynchronous Tasking (HiHAT) effort.

	We are currently in the first phase of the development of this framework, in which we are		We are currently in the first phase of the development of this framework, in which we are
Line 5:		Line 5:
	* Building momentum toward a production-quality, retargetable framework for broad community use		* Building momentum toward a production-quality, retargetable framework for broad community use
	* Gathering usage models and requirements in the form of user stories with acceptance criteria		* Gathering usage models and requirements in the form of user stories with acceptance criteria
	* Identifying representative and influential applications that serve as poster children for ~~HHAT~~, and developers who are ready to invest in good software engineering to produce an effective, durable, scalable and retargetable result		* Identifying representative and influential applications that serve as poster children for HiHAT, and developers who are ready to invest in good software engineering to produce an effective, durable, scalable and retargetable result

	Sign up at the [[https://www.eventbrite.com/e/heterogeneous-hierarchical-asynchronous-tasking-hhat-startup-tickets-30237046821\|Eventbrite site]] to get an invite to regular meetings, whose MINUTES are kept [[HHAT Usage Meeting Minutes\|HERE]].		Sign up at the [[https://www.eventbrite.com/e/heterogeneous-hierarchical-asynchronous-tasking-hhat-startup-tickets-30237046821\|Eventbrite site]] to get an invite to regular meetings, whose MINUTES are kept [[HHAT Usage Meeting Minutes\|HERE]].

	This wiki presently serves to inform the development of a ~~HHAT~~ framework in four ways:		This wiki presently serves to inform the development of a HiHAT framework in four ways:
	# [[Glossary and References]]		# [[Glossary and References]]
	# [[Usage models]]		# [[Usage models]]
	#* prosaic descriptions of how ~~HHAT~~ would be used		#* prosaic descriptions of how HiHAT would be used
	#* Examples: static vs. dynamic, C++ features, task graph vs. imperative interfaces, multiple files vs. one source file		#* Examples: static vs. dynamic, C++ features, task graph vs. imperative interfaces, multiple files vs. one source file
	#* purpose: get a deeper appreciation of new usages, see commonalities and patterns across multiple usages		#* purpose: get a deeper appreciation of new usages, see commonalities and patterns across multiple usages
Line 30:		Line 30:
	* This is a community effort. It is expected that the whole community will benefit from the considerable efforts of many generous and conscientious people who are working for the common good. Thanks for your investment!		* This is a community effort. It is expected that the whole community will benefit from the considerable efforts of many generous and conscientious people who are working for the common good. Thanks for your investment!

	At this point, ~~HHAT~~ is a descriptive handle, rather than a proper name. ~~For~~ a ~~HHAT framework to be viable, it needs to support several targets, provide common building blocks, services and transformations in an open architecture, and enable a variety of different applications~~ and ~~frameworks to be built on top~~. ~~The diagram below suggests one possible arrangement~~.		At this point, HiHAT is a descriptive handle, rather than a proper name. It does suggest a top-down and bottom-up approach. Being able to wear many hats is suggestive of the many user-facing interfaces.

	[[File:HHAT_Diagram.jpg\|center\|600px\|caption="Possible ~~HHAT~~ architecture"]]		For a HiHAT framework to be viable, it needs to support several targets, provide common building blocks, services and transformations in an open architecture, and enable a variety of different applications and frameworks to be built on top. The diagram below suggests one possible arrangement.

			[[File:HHAT_Diagram.jpg\|center\|600px\|caption="Possible HiHAT architecture"]]

	If the middle layers are modular, implementations can be created, plugged in, and iteratively refined. They may be freely shared or premium versions could be offered commercially.		If the middle layers are modular, implementations can be created, plugged in, and iteratively refined. They may be freely shared or premium versions could be offered commercially.

imported>Cnewburn at 18:29, January 17, 2017

2017-01-17T18:29:30Z

← Older revision		Revision as of 18:29, January 17, 2017
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	* Identifying representative and influential applications that serve as poster children for HHAT, and developers who are ready to invest in good software engineering to produce an effective, durable, scalable and retargetable result		* Identifying representative and influential applications that serve as poster children for HHAT, and developers who are ready to invest in good software engineering to produce an effective, durable, scalable and retargetable result

	Sign up at the [[https://www.eventbrite.com/e/heterogeneous-hierarchical-asynchronous-tasking-hhat-startup-tickets-30237046821\|Eventbrite site]] to get an invite to regular meetings, whose ~~minutes~~ are kept [[HHAT Usage Meeting Minutes\|~~here~~]].		Sign up at the [[https://www.eventbrite.com/e/heterogeneous-hierarchical-asynchronous-tasking-hhat-startup-tickets-30237046821\|Eventbrite site]] to get an invite to regular meetings, whose MINUTES are kept [[HHAT Usage Meeting Minutes\|HERE]].

	This wiki presently serves to inform the development of a HHAT framework in four ways:		This wiki presently serves to inform the development of a HHAT framework in four ways:

imported>Luszczek: Move to user stories

2017-01-17T16:51:37Z

Move to user stories

← Older revision		Revision as of 16:51, January 17, 2017
Line 35:		Line 35:

	If the middle layers are modular, implementations can be created, plugged in, and iteratively refined. They may be freely shared or premium versions could be offered commercially.		If the middle layers are modular, implementations can be created, plugged in, and iteratively refined. They may be freely shared or premium versions could be offered commercially.


	~~= Language Bindings =~~

	~~== C ==~~

	~~For maximum portability, C offers the most portable ABI that can easily serve~~
	~~other compiled languages as well as interpreters of scripting languages.~~
	~~The only way to break the C ABI is to use more exotic types such as extended~~
	~~precision numbers so we should avoid it.~~

	~~== C++ ==~~

	~~C++ bindings may get complicated: object structure for one hardware may not make~~
	~~sense on another platform.~~

	~~''MPI deprecated C++ bindings for some time now. What's left are bindings provided~~
	~~by Boost which might be an overkill for some applications.''~~

	~~== Fortran ==~~

	~~Fortran 2003 seems to be OK with calling C directly. But the actual Fortran module~~
	~~with binding specification. Some C data types might be prohibited.~~

	~~''Lessons learned from the MPI standard: decide whether we use pointers or integer handles.~~
	~~Also, asynchronous interfaces break Fortran's rule of local variables not being changed~~
	~~after a function returns as in:''~~

	~~MPI_Isend(&var);~~
	~~// 'var' will be changed here~~
	~~MPI_Wait()~~
	~~// MPI does not change to 'var' any longer''~~

imported>Luszczek: Move glossary to its own page where it belongs

2017-01-17T16:41:47Z

Move glossary to its own page where it belongs

← Older revision		Revision as of 16:41, January 17, 2017
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	This wiki presently serves to inform the development of a HHAT framework in four ways:		This wiki presently serves to inform the development of a HHAT framework in four ways:
	# [[Glossary and References]]		# [[Glossary and References]]
	~~## Tasklet - Non-decomposable task~~
	~~## Task - May be split into one or many tasks.~~
	~~## Data Source - Originator of data communication~~
	~~## Data Sink - Destination for data communication~~
	## Directory - Look up service to identify a sink or source in a lower-level communication substrate. ''It might be wise to externalize a global directory service and make it an optional part of the reference implementation. By so doing, we allow a cottage industry to create competing implementation of such look-up services that serve specific needs of applications, hardware, or the middleware.''
	# [[Usage models]]		# [[Usage models]]
	#* prosaic descriptions of how HHAT would be used		#* prosaic descriptions of how HHAT would be used

imported>Luszczek: Moved "concepts" to glossary bullet

2017-01-17T16:39:54Z

Moved "concepts" to glossary bullet

@@ Line 11: / Line 11: @@
 This wiki presently serves to inform the development of a HHAT framework in four ways:
 # [[Glossary and References]]
 # [[Usage models]]
 #* prosaic descriptions of how HHAT would be used
@@ Line 67: / Line 72: @@
   MPI_Wait()
   // MPI does not change to 'var' any longer''

imported>Luszczek: initial guidelines for C++ bindings

2017-01-17T05:40:50Z

initial guidelines for C++ bindings

← Older revision		Revision as of 05:40, January 17, 2017
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	== C++ ==		== C++ ==

			C++ bindings may get complicated: object structure for one hardware may not make
			sense on another platform.

			''MPI deprecated C++ bindings for some time now. What's left are bindings provided
			by Boost which might be an overkill for some applications.''

	== Fortran ==		== Fortran ==

imported>Luszczek: fix code formatting

2017-01-17T05:38:27Z

fix code formatting

← Older revision		Revision as of 05:38, January 17, 2017
Line 55:		Line 55:
	''Lessons learned from the MPI standard: decide whether we use pointers or integer handles.		''Lessons learned from the MPI standard: decide whether we use pointers or integer handles.
	Also, asynchronous interfaces break Fortran's rule of local variables not being changed		Also, asynchronous interfaces break Fortran's rule of local variables not being changed
	after a function returns as in:		after a function returns as in:''
	MPI_Isend(&var);
	// 'var' will be changed here		MPI_Isend(&var);
	MPI_Wait()		// 'var' will be changed here
	// MPI does not change to 'var' any longer''		MPI_Wait()
			// MPI does not change to 'var' any longer''

	= Concepts in Lower Layer =		= Concepts in Lower Layer =

imported>Luszczek: Initial comments on Fortran bindings

2017-01-17T05:36:56Z

Initial comments on Fortran bindings

← Older revision		Revision as of 05:36, January 17, 2017
Line 49:		Line 49:

	== Fortran ==		== Fortran ==

			Fortran 2003 seems to be OK with calling C directly. But the actual Fortran module
			with binding specification. Some C data types might be prohibited.

			''Lessons learned from the MPI standard: decide whether we use pointers or integer handles.
			Also, asynchronous interfaces break Fortran's rule of local variables not being changed
			after a function returns as in:
			MPI_Isend(&var);
			// 'var' will be changed here
			MPI_Wait()
			// MPI does not change to 'var' any longer''

	= Concepts in Lower Layer =		= Concepts in Lower Layer =