chapel Overview

Chapel is an emerging parallel programming language being developed by Cray Inc. with the goal of improving programmer productivity. Chapel’s implementation is very much a work-in-progress and one that Cray is undertaking in an open-source manner at SourceForge under the BSD license. The following information is available by running module help chapel 
Now Available: Cray Chapel Compiler 1.4.0


   Cray is pleased to announce the release of version 1.4.0 of the
   Cray Chapel Compiler.  Chapel is an emerging parallel programming
   language designed to improve productivity of high-end computer
   users while also serving as a portable parallel programming model
   for use on commodity clusters or desktop multicore systems.


Chapel 1.4.0
============

    Chapel is an emerging parallel programming language being
    developed by Cray Inc. with the goal of improving programmer
    productivity.  Chapel's implementation is very much a
    work-in-progress and one that Cray is undertaking in an
    open-source manner at SourceForge under the BSD license.  We
    encourage feedback from potential users in order to help improve
    Chapel's usefulness, generality, and adoptability.  We are also
    interested in seeking out mutually beneficial collaborations with
    external research groups.

    The highlights of this release include: New optimizations for
    whole-array assignments and remote array accesses; new 'export'
    and 'extern' keywords for interoperability; improved support for
    Qthreads and Nanos+++ tasking, including multi-locale execution;
    dynamic work partitioning iterators for ranges; new and improved
    example codes; improvements to the language specification; and
    numerous feature improvements and bug fixes.  See
    $CHPL_HOME/CHANGES for a more complete list of changes.

    This release of Chapel contains stable support for the base
    language, and for task and regular data parallelism using one or
    more locales.  Data parallel operations on irregular domains and
    arrays are currently supported in a single-locale implementation.
    While performance has received a great deal of attention in
    Chapel's design, this release lacks a number of crucial
    performance optimizations and is not suitable for in-depth
    performance comparisons and studies.

    To get started with Chapel, load the chapel module and refer to
    $CHPL_HOME/README for 'Quick Start' instructions and pointers to
    next steps, including example programs, the language
    specification, and further documentation.  Unimplemented features
    and known bugs can be found in $CHPL_HOME/STATUS and a full list
    of changes since the previous release can be found in
    $CHPL_HOME/CHANGES.  Users of Chapel are expected to read and
    comply with the user agreement contained in $CHPL_HOME/AGREEMENT.

    For more information on Chapel beyond what's contained in the
    release, please refer to the Chapel web page at:
    http://chapel.cray.com

    Interested users are encouraged to join the Chapel users' mailing
    list, chapel-users@lists.sourceforge.net.  Questions about Chapel
    can be directed to the Chapel team at chapel_info@cray.com.  Bug
    reports that can be made publicly visible should be directed to
    chapel-bugs@lists.sourceforge.net; private bugs can be mailed to
    chapel_bugs@cray.com.


How Do I Get It?
----------------

    The Chapel 1.4.0 release is available for download at these URLs:

    http://crayport.cray.com/Pages/default.aspx 
    http://www.sourceforge.net/projects/chapel


Deliverables:
-------------

   The Chapel release packages contain the compiler executables,
   runtime libraries, example programs, and documentation for use on
   Cray XT (TM) and Cray XE (TM) systems.  Additional information and 
   the source release can be found at: http://chapel.cray.com and
   http://www.sourceforge.net/projects/chapel


Schedule:
---------

   Official release date          October 20, 2011
   Chapel 1.5.0 release           April 2012


Licensing:
----------

    Chapel is licensed under the terms of the BSD license.  See
    http://chapel.cray.com/release/LICENSE for details.


Dependencies:
-------------

    The Chapel 1.4.0 release is supported on Cray XT systems running the
    UNICOS/lc 2.0 CNL and CLE 2.1 or later operating systems and
    Cray XE systems running CLE 3.1UP00 CNL or later operating system.

    A back-end C compiler is required to generate an executable.  
    Any recent version of PrgEnv-cray, PrgEnv-pgi, PrgEnv-gnu,
    or PrgEnv-intel can be used.


Installation instructions:
--------------------------

   Copy the Chapel 1.4.0 RPM file to the current directory and execute
   one of the following commands:

     #On Cray XE systems:
     rpm -ivh chapel-1.4.0-gem3.x86_64.rpm 

     #On Cray XT systems:
     rpm -ivh chapel-1.4.0-ss3.x86_64.rpm

     To make Chapel 1.4.0 the default version, execute:
      /opt/cray/admin-pe/set_default_files/set_default_chapel_1.4.0


Getting started:
----------------

   Please see $CHPL_HOME/README for quick start information.


Known Problems:
---------------

   Unimplemented features and known problems are documented in
   $CHPL_HOME/STATUS

==================================================================

To re-display chapel/1.4.0 release information,
type:    less /opt/chapel/1.4.0/gemini/release_info
==================================================================
Support

Usage

First load the chapel module 
$ module load chapel
Next, now that the compiler executable is available in the PATH. Chapel has built in support for multi-threading/parallel programming. This can be seen in the following example: 
config const numTasks = here.maxTaskPar;
forall tid in 0..#numTasks do
  writeln("Hello from task " + tid);
Config variables, like numTasks can be set at runtime by passing the executable the --numTasks=<number of processes>. Next, the forall loop is automatically parallelized by the Chapel compiler to run on multicore CPUs (this is NOT GPU parallelization).  To compile the source into an executable, run: 
$ chpl -o source source.chpl
This will output two executables: source and source_real. The first is a wrapper that will execute the appropriate aprun command. When running a Chapel executable, be sure to pass it the -nl or --numLocales= flag with the appropriate number of nodes you want used. Other available flags and config variables can be viewed by running ./source --help. 
$ ./source -nl8 --numTasks=16
For example, this is the equivilant of launching: 
$ aprun -cc none -d16 -n8 -N1 -j0 ./source_real -v -nl8 --numTasks=16
The result will look something like this: 
Hello from task 2 of 16
Hello from task 4 of 16
Hello from task 8 of 16
Hello from task 0 of 16
Hello from task 6 of 16
Hello from task 12 of 16
Hello from task 14 of 16
Hello from task 10 of 16
Hello from task 3 of 16
Hello from task 5 of 16
Hello from task 9 of 16
Hello from task 1 of 16
Hello from task 7 of 16
Hello from task 13 of 16
Hello from task 15 of 16
Hello from task 11 of 16
Builds

TITAN

  • 1.10.0

EOS

  • 1.10.0