Main Page

Welcome to the wiki pages for the Hierarchical Heterogeneous Asynchronous Tasking effort.

Sign Up & Join

• Request a New Account
• Forgotten Password
• User's Guide

Discussions

Hedgehog

Meetings

HiHAT Meeting Minutes

HiHAT Presentations

Events

News

New Call for Centres of Excellence for HPC Applications	18-Sep-23
Lenovo is Still the No1 Global Provider of Supercomputers	05-Jun-23

Main Page

About this Wiki

This wiki presently serves to inform the development of a HiHAT framework in seven ways:

1. Glossary and References
2. 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
3. User stories
   • formulaic, succinct and more rigorous descriptions of what is wanted out of HiHAT
   • As a <role>, I want <function> so that <benefit>, such that <acceptance criteria>
   • purpose: get more rigorous about what is needed
4. 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 HiHAT
   • 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 HiHAT
   • 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
5. Runtime Clients
   • Language or tasking runtimes that are clients on top of the HiHAT user and common layers
   • Descriptions, key characteristics
6. Implementation Modules
   • Implementations of HiHAT user and common layer functionality, provided by vendors or third parties
7. Reference
   • pointers to other related work that could be of interest to this community that doesn't fit into the above categories

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!

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.

Please refer to the HiHAT SW Stack page for a discussion of how various SW components might interact.

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.