Barrier コマンドは、Launch コマンドにより起動されたジョブの全てを、その全プロセスが Barrier コマンドを実行し終わるまでブロックします。

これは、実行を同期するのに便利です。ノード 0 が、他の全ノードの処理が完了するまで強制的に待機させることができます。

この関数は、現在のところ hpc モードでは利用できません。

Grid[Barrier] コマンドは、Maple 15 より導入されました。

Maple 15 の変更点についての詳細は、Maple 15 の更新情報 をご覧ください。

dosome := proc()
   uses Grid;
   local i, me;
   me := MyNode();
   for i from 1 to 10^(me+3) do
       if i mod 10^5 = 0 then
           print(me,i);
       end if;
   end do;
   print(me,"done");
end proc:

Grid[Launch](dosome,numnodes=4);

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               0, "done"

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               1, "done"

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               2, 100000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               2, "done"

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 100000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 200000

doall:= proc()
   uses Grid;
   local i, me;
   me := MyNode();
   for i from 1 to 10^(me+3) do
       if i mod 10^5 = 0 then
           print(me,i);
       end if;
   end do;
   print(me,"done");
   Barrier();
end proc:

Grid[Launch](doall,numnodes=4);

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               0, "done"

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               1, "done"

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               2, 100000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               2, "done"

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 100000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 200000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 300000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 400000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 500000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 600000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 700000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 800000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, 900000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              3, 1000000

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               3, "done"