The Chapel Parallel Programming Language


CHIUW 2015

2nd Annual Chapel Implementers and Users Workshop

Saturday-Sunday, June 13-14, 2015
Oregon Convention Center (room A107-A108), Portland, OR
(a PLDI 2015 / FCRC 2015 workshop)

Advance Program

CHIUW 2015—the ACM SIGPLAN second annual Chapel Implementers and Users Workshop—is the second in an annual series of workshops designed to bring developers and users of the Chapel language ( together to report on work being done with the language across the broad open-source community. Attendance is open to anyone interested in Chapel, from the most seasoned Chapel user or developer to someone simply curious to learn more.


Registration: See the FCRC registration site (select 1- or 1.5-day workshop).


Saturday, June 13, 2015 (Full Day)

8:15 - 9:00:  Breakfast (catered by PLDI)
8:30 - 9:00:  Chapel Boot Camp (Optional) [slides]
Brad Chamberlain (Cray Inc.)
This is a completely optional primer session prior to the official workshop start (pending access to the room) for those who are new to Chapel or would like a refresher.
9:00 - 9:30:  Welcome, State of the Project [slides]
Brad Chamberlain (Cray Inc.)
Technical Talks
Session chair: Mauricio Breternitz (AMD)
9:30 - 10:00: Practical Diamond Tiling for Stencil Computations Using Chapel Iterators [extended abstract | slides]
Michelle Mills Strout, Ian J. Bertolacci, and Catherine Olschanowsky (Colorado State University), Ben Harshbarger and Brad Chamberlain (Cray Inc.), David G. Wonnacott (Haverford College)
10:00 - 10:30: A Study of Red-Black SOR Parallelization Using Chapel, D, and Go Languages [extended abstract | slides]
Sparsh Mittal (Oak Ridge National Lab)
10:30 - 11:00: Data-Centric Locality in Chapel [extended abstract | slides]
Ben Harshbarger (Cray Inc.)
11:00 - 11:30:  Break (catered by PLDI)
Technical Talks (continued)
Session chair: Michelle Strout (CSU)
11:30 - 12:00: Parallac: Using Chapel with ARM Clusters [extended abstract | slides]
Brian Guarraci (Twitter Inc.)
12:00 - 12:30: Hierarchical Locale Models in Chapel [extended abstract | slides]
Sung-Eun Choi, David Iten, Elliot Ronaghan, Greg Titus (Cray Inc.)
12:30 - 2:00:  Lunch (catered by PLDI)
Keynote Talk
Session chair: Brad Chamberlain
2:00 - 3:00:  Shared Memory HPC Programming: Past, Present, and Future [slides]
William Carlson (IDA)
Bio: William Carlson is a member of the research staff at the IDA Center for Computing Sciences where, since 1990, his focus has been on applications and system tools for large-scale parallel and distributed computers. He also leads the UPC language effort, a consortium of industry and academic research institutions aiming to produce a unified approach to parallel C programming based on global address space methods.
Technical Talks (continued)
Session chair: Dylan Stark (Sandia)
3:00 - 3:30: Vectorization of Chapel Code [extended abstract | slides]
Elliot Ronaghan (Cray Inc.)
3:30 - 4:00:  Break (catered by PLDI)
Hot Topics Talks
Session chair: Greg Titus (Cray)
4:00 - 4:10: The Chapel Memory Consistency Model [abstract | slides]
Sung-Eun Choi, Michael Ferguson, Elliot Ronaghan, Greg Titus (Cray Inc.)
4:10 - 4:20: Fast Fourier Transforms in Chapel [abstract | slides]
Doru Thom Popovici, Franz Franchetti (Carnegie-Mellon University)
4:20 - 4:30: A Preliminary Performance Comparison of Chapel to MPI and MPI/OpenMP [abstract | slides]
Laura Brown (US Army Engineer Research and Development Center)
4:30 - 4:40: Data flow programming—a high performance and highly complicated programming concept? [abstract | slides]
Jens Breitbart (Technische Universität München)
4:40 - 4:50: If you can dodge a wrench, you can dodge a ball [abstract | slides]
Dylan Stark, George Stelle (Sandia National Laboratories)
4:50 - 5:00: A Progress Report on COHX: Chapel on HSA + XTQ [abstract | slides]
Mauricio Breternitz, Bibek Ghimire, Mike Chu, Steve Reinhardt (Advanced Micro Devices (AMD))
Community Discussion / Wrap-up
Session Chair: Tom MacDonald
5:00 - 6:00:  Community Discussion [slides]
To wrap up the day, we'll have an open discussion about Chapel's future, priorities, adoption, or anything else of interest to those in attendance.
6:00 -       :  Adjourn for Dinner (in ad hoc groups or on your own)

Sunday, June 14, 2015 (Half Day)

Chapel Code Camp
9:00 - 12:30:  Chapel Code Camp
This half-day will be spent doing pair-/group-programming exercises as a means of helping Chapel users and developers benefit from each others' experience. Currently planned activities include:
  • Active Libraries in Chapel
  • Data Processing workloads in Chapel
  • Active Message Data Transfer optimizations
  • Code Generation for HSA (via LLVM?)
  • Libraries for plotting, image processing, linear algebra, ...
  • native FFTs in Chapel
  • ZeroMQ
If you're interested in seeing additional topics added to this list, see the Call for Participation or let us know at the workshop.
12:30 - whenever:  Lunch (catered by PLDI)



General Chair: Tom MacDonald, Cray Inc.

Program Committee:


Call For Participation (for archival purposes)