Type of Talk: UTCS Colloquium

Speaker/Affi

liation: Brad Chamberlain/Cray Inc.

Date/Time: Tuesday June 3 20

08 4:15 p.m.

Location: ACES 2.402

Host: Calvin Lin

T

alk Title: Chapel: the Cascade High Productivity Language

Talk Abst

ract
Chapel is a new programming language being developed by
Cray In

c. as part of the DARPA-led High Productivity Computing
Systems program
(HPCS). Chapel strives to increase productivity
for supercomputer use

rs by supporting higher levels of abstraction
compared to current paral

lel programming models while also
supporting the ability to optimize to
performance that meets or
surpasses current technologies. Chapel lang

uage concepts that
help with parallel programmability include globally-

distributed data
aggregates and anonymized task-based parallelism. Perf

ormance
tuning is supported through features that support specification
of
and reasoning about locality on target parallel architectures. In

contrast to previous higher-level parallel languages Chapel is
des

igned to be a multiresolution language in which users can
begin by wri

ting very abstract code and then incrementally add
more detail until th

ey are as close to the machine as their needs
require. In this talk I
will provide an overview of Chapel explain
its context and philosophy
and describe the project''s status.

Future research challenges w

ill be given and opportunities for
collaboration suggested.

Spea

ker Bio
Bradford Chamberlain is a Principal Engineer at Cray Inc. where

he works on parallel programming models focusing primarily on
the
design and implementation of the Chapel parallel language in
his role

as technical lead for that project. Before starting at Cray
in 2002 h

e spent a year at a start-up working at the opposite end
of the hardwar

e spectrum to design a parallel language (SilverC)
for reconfigurable e

mbedded hardware. Brad received his Ph.D. in
Computer Science & Enginee

ring from the University of Washington
in 2001 where his work focused o

n the design and implementation
of the ZPL parallel array language par

ticularly on implementing and
generalizing its region concept--a first-c

lass index set representation
for programming with distributed arrays.
While at UW he also
dabbled in algorithms for accelerating the render

ing of complex 3D
scenes. Brad remains associated with the University o

f Washington
as an affiliate faculty member and most recently co-led a

seminar
there that focused on the design of Chapel. He received his Ba

chelor''s
degree in Computer Science from Stanford University with hono

rs in 1992.