Global Arrays

{{Infobox programming language

| name = Global Arrays (GA)

| logo =

| paradigm = parallel, one-sided message passing, imperative (procedural), structured

| year = 1994

| designer =

| developer =

| latest_release_version = 5.8.2/{{release date|2022|11}}

| typing = static, weak

| implementations =

| dialects =

| influenced_by =

| influenced =

| operating_system = Cross-platform

| website = {{URL|1=http://hpc.pnl.gov/globalarrays/}}

| file_ext =

}}

Global Arrays, or GA, is the library developed by scientists at Pacific Northwest National Laboratory for parallel computing. GA provides a friendly API for shared-memory programming on distributed-memory computers for multidimensional arrays. The GA library is a predecessor to the GAS (global address space) languages currently being developed for high-performance computing.

{{cite journal

|title=Shared Memory Programming in Metacomputing Environments: The Global Array Approach

|last1=Nieplocha

|first1=Jarek

|last2=Harrison

|first2=Robert

|journal=The Journal of Supercomputing

|volume=11

|pages=119–136

|year=1997

|doi=10.1023/A:1007955822788

|issue=2|s2cid=27322677

}}

{{cite journal

|last1=Nieplocha

|first1=Jarek

|title=Advances, Applications and Performance of the Global Arrays Shared Memory Programming Toolkit

|journal=International Journal of High Performance Computing Applications

|volume=20

|pages=203–231

|year=2006

|doi=10.1177/1094342006064503

|issue=2|citeseerx=10.1.1.133.9926

|s2cid=116634

}}{{cite journal

|last1=Nieplocha

|first1=Jaroslaw

|last2=Harrison

|first2=Robert J.

|last3=Littlefield

|first3=Richard J.

|title=Global arrays: A nonuniform memory access programming model for high-performance computers

|journal=The Journal of Supercomputing

|volume=10

|year=1996

|doi=10.1007/BF00130708|pages=169–189

|issue=2|citeseerx=10.1.1.41.5891

|s2cid=1272614

}}

{{cite book

|isbn = 978-1-58603-796-3

|editor1-last = Bischof

|editor1-first = Christian

|editor2-last = Bücker

|editor2-first = Martin

|editor3-last = Gibbon

|editor3-first = Paul

|editor4-last = Joubert

|editor4-first = Gerhard R.

|editor5-last = Lippert

|editor5-first = Thomas

|editor6-last = Mohr

|editor6-first = Bernd

|editor7-last = Peters

|editor7-first = Frans

|title = Parallel Computing: Architectures, Algorithms and Applications

|year = 2008

|volume = 15

|pages = 339–345

|publisher = IOS Press

|location = Amsterdam

|issn = 0927-5452

|oclc = 226966397

|chapter = Towards Fault Resilient Global Arrays

|series = Advances in Parallel Computing

|last1 = Tipparaju

|first1 = Vinod

|last2 = Krishnan

|first2 = Manoj

|last3 = Palmer

|first3 = Bruce

|last4 = Petrini

|first4 = Fabrizio

|last5 = Nieplocha

|first5 = Jarek

|chapter-url = http://www.booksonline.iospress.nl/Content/View.aspx?piid=8409

|access-date = 2012-07-17

|archive-date = 2021-03-06

|archive-url = https://web.archive.org/web/20210306202659/http://www.booksonline.iospress.nl/Content/View.aspx?piid=8409

|url-status = live

}}

The GA toolkit has additional libraries including a Memory Allocator (MA), Aggregate Remote Memory Copy Interface (ARMCI), and functionality for out-of-core storage of arrays (ChemIO). Although GA was initially developed to run with TCGMSG, a message passing library that came before the MPI standard (Message Passing Interface), it is now fully compatible with MPI. GA includes simple matrix computations (matrix-matrix multiplication, LU solve) and works with ScaLAPACK. Sparse matrices are available but the implementation is not optimal yet.

GA was developed by Jarek Nieplocha, Robert Harrison, R. J. Littlefield, Manoj Krishnan, and Vinod Tipparaju. The ChemIO library for out-of-core storage was developed by Jarek Nieplocha, Robert Harrison and Ian Foster.

The GA library is incorporated into many quantum chemistry packages, including NWChem, MOLPRO, UTChem, MOLCAS, and TURBOMOLE. The GA library is also incorporated into sub-surface code [http://stomp.pnnl.gov/ STOMP] {{Webarchive|url=https://web.archive.org/web/20130213232020/http://stomp.pnnl.gov/ |date=2013-02-13 }}{{Cite web|url=http://hpc.pnl.gov/globalarrays/performance.shtml|title=Gordon Bell Finalist at SC09 - GA Crosses the Petaflop Barrier|year=2009|work=PNNL|access-date=2015-05-23|archive-date=2013-02-22|archive-url=https://web.archive.org/web/20130222081652/http://www.emsl.pnl.gov/docs/global/performance.shtml|url-status=live}}

The GA toolkit is free software, licensed under a [http://hpc.pnl.gov/globalarrays/license.shtml self-made license] {{Webarchive|url=https://web.archive.org/web/20190405154446/http://hpc.pnl.gov/globalarrays/license.shtml |date=2019-04-05 }}.