Dual Parfor from different scripts

2023 2 1
1 个回答
回答已采纳
更新时间：2023 2 2
8 次查看（30 天）

0 个投票

So I have a Launcher.m script which executes a function.m using parfor. The function.m also has its own parfor. Will this work?

请先登录，再回答此问题。

 采纳的回答

Walter Roberson
Walter Roberson 2023-2-1
编辑：Walter Roberson 2023-2-2

1 个投票

https://www.mathworks.com/help/parallel-computing/nested-parfor-loops-and-for-loops.html
it will be accepted but will execute the second one in serial order

4 个评论
显示 2更早的评论 隐藏 2更早的评论

That was quick, thank you.
Is there a way to run both the parfors. The function.m uses parfor within. That must be driven for values [1, 2, 3, 4, 4.2, 4.4, 4.6, 4.8] for which I use parfor?
Walter Roberson
Walter Roberson 2023-2-2
The nested parfor will be executed in serial, in reverse order. It is not possible to initiate parallel constructs within parallel constructs and have the nested ones operate in parallel.
(Though I am not certain what would happen if you were to parfeval() or batch() within a parallel construct.)
Walter Roberson
Walter Roberson 2023-2-2
Ran in:
Ran in:
Looks like parfeval() and parfor() cannot initiate parfeval() ...
p = parpool();
Starting parallel pool (parpool) using the 'Processes' profile ... Connected to the parallel pool (number of workers: 2).
outer_results = parfevalOnAll(p, @test_outer, 0, p)
outer_results =
FevalOnAllFuture with properties: ID: 5 Function: @test_outer CreateDateTime: 02-Feb-2023 02:33:51 StartDateTime: 02-Feb-2023 02:33:51 RunningDuration: 0 days 0h 0m 0s State: running Error: [1x2 cell]
celldisp(outer_results.Error)
ans{1} = ParallelException with properties: identifier: 'MATLAB:parallel:future:NoFevalOnWorkers' message: 'Workers cannot execute parfeval or parfevalOnAll.' cause: {} remotecause: {[1×1 MException]} stack: [2×1 struct] Correction: [] ans{2} = ParallelException with properties: identifier: 'MATLAB:parallel:future:NoFevalOnWorkers' message: 'Workers cannot execute parfeval or parfevalOnAll.' cause: {} remotecause: {[1×1 MException]} stack: [2×1 struct] Correction: []
parfor K = 1 : p.NumWorkers
test_outer(p);
end
Analyzing and transferring files to the workers ...done. outer about to start inner, ID = 67
Error using parallel.ProcessPool/parfevalOnAll
Workers cannot execute parfeval or parfevalOnAll.

Error in solution>test_outer (line 13)
inner_results = parfevalOnAll(p, @test_inner, 0, ID)
function test_outer(p)
ID = randi(99);
fprintf('outer about to start inner, ID = %d\n', ID);
inner_results = parfevalOnAll(p, @test_inner, 0, ID)
celldisp(inner_results.Error)
fprintf('outer fininished inners, ID = %d\n', ID);
end
function test_inner(ID)
subID = randi(99);
fprintf('inner ID %d subid %d reporting!\n', ID, subID);
end

请先登录，再进行评论。

更多回答（0 个）

类别

在 帮助中心 和 File Exchange 中查找有关 Parallel Computing Fundamentals 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by