Questions on parallel computing in Mathematica.

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2
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1answer
107 views

ParallelEvaluate: Evaluation Rules and Increment

I'm trying to understand how ParallelEvaluate works, considering the two following snippets: ...
2
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1answer
176 views

Understanding a slowdown associated with wrapping a set of nested Do loops with a ParallelDo expression

I have a set of set of nested Do loops that require data from three different arrays (though the position from each array is fixed per cycle of the outer Do loop). Let's call these arrays: ListA, ...
2
votes
1answer
97 views

How can I set the kernel for CreatePalette?

I have written some code that requests some calculations from an SQL server every N seconds and uses a palette: CreatePalette[Dynamic[DateListPlot[...]]] I ...
2
votes
1answer
366 views

Light Weight Grid and core limitation

I am trying to figure out what would be best for running some simulations using multiple computers where each has it's own mma 8 licence. The main part of the computation involves a parallelized table ...
2
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1answer
260 views

Clearing distributed definitions from remote kernels

The documentation shows the following example to "Remove a distributed definition..." Oh, course this doesn't work without redefining the function prior to re distributing the definition. The ...
2
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1answer
75 views
2
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1answer
124 views

ParallelTable slowdown for a task involving ComponentMeasurements

I'm having trouble understanding a slowdown associated with code I'm running, which should be trivial to parallelize. My code looks something like this: ...
2
votes
1answer
42 views

Dynamic Output during ParallelMap

I can't seem to figure out how to dynamically output a variable that is being used in a parallel evaluation. Below is an example function that demonstrates my problem. ...
2
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1answer
59 views

Button action preventing parallel execution?

I couldn't find a better title, so I'll jump straight to the example! There is this long list of slow jobs to be executed in a parallel way, at the press of a button: ...
2
votes
1answer
118 views

Launching external program in background process with ParallelSubmit

I work on the implementation of an image processing pipeline in Mathematica in which I also would like to use external programs to do certain processing steps. As an example I have macros for the ...
2
votes
2answers
171 views

Definitions inside ParallelTable?

How can I make definitions inside ParallelTable to use them outside? For example, if I execute: ...
2
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2answers
169 views

Executing several input cell simultaneously with parallelization

How can I execute more than one input cell simultaneously using different processor. For example consider this two cells ...
2
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1answer
242 views

How to parallel this nested table efficiently?

I have an 8 core CPU and want to parallel evaluate the following nested Table Table[Table[expr[i,j], {i,1,10}], {j,1,4}] But ...
2
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1answer
250 views

How can I prevent these warnings while using ParallelTable

I have this code to find all the permutations of a set of letters that form legal words. ...
2
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1answer
115 views

Parallel computing NInverseFourierTransForm

I am running the code below, and it works perfectly. I have some function in Fourier space, and I take the numerical InverseFourierTransform. However, I will have ...
2
votes
1answer
71 views

How to access directly the “CUDA Memory” address from another parallel kernel?

I work with CUDALink and have some small successes. I use direct calculation on GPU without using CPU (only for sanding commands for CUDA function). Until now I have stored on the hard drive with ...
2
votes
1answer
77 views

Intensive test parallel computation?

I need an example of a not-too-complicated yet intensive parallel computation in Mathematica. The result of the computation should be known before hand. I need this to test the capabilities of a ...
2
votes
1answer
118 views

How to parallelize the most outer loop only?

I have two Doloops. The outer loop iterate over the inner loop. The inner loop contains a set of step by step instructions which each next step depends on the ...
2
votes
1answer
55 views

Lightweight Grid saving to file

I'm trying to launching my first jobs on LightWeight Grid using ParallelDo. I have 10000 jobs, each of which returns a 1M output, which I would like saved to a file on the head machine, one file per ...
2
votes
1answer
258 views

Remote Kernel Setup: SSH fails with exit code 32512

I am having trouble with configuring parallel kernels. What I want to do is the following: run remote kernels on my home server to which I would like to connect from work using my laptop. Both ...
2
votes
1answer
64 views

Parallelization and evaluation of random number generation

Suppose I have the following functions: ...
2
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1answer
133 views

SSH known hosts in Windows (Error code = 124)

I had to re-install Raspbian OS and now it has new SSH key. SSH clients usually let ignore this fact and save the new key, but not now. Mathematica gives no way to go if the Host Key was changed. I ...
2
votes
1answer
185 views

Server running WolframLightWeightGrid manager loses licensing information

"Once more into the breach..," I have 2 identical Xserves running OS X Server 10.6.8 each with 2 quad core Intel Xenon processors a total of 16 kernels. I have configured both servers identically ...
2
votes
1answer
242 views

how to nest parallelized computations on a cluster?

I am lucky to have access to a computational cluster and I could submit my job to many-many cores. As I need to evaluate a numerical integral within a numerical integral, I would like to know if I can ...
2
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0answers
22 views

ParallelSubmit and WaitNext: check if a job is done before calling WaitNext

Say I process something with ParallelSubmit: LaunchKernels[] job = ParallelSubmit[1 + 2] Parallel`Developer`QueueRun[] Then, I will use ...
2
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0answers
59 views

What was the thought behind the parallel versions of Table, Map, etc..?

There separately named versions of the parallel analogues of Map[] and friends: ...
2
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0answers
88 views

Bug in parallel computing

The following is a simplified example. We construct a library function f and another library function g, in which the library function f is called. ...
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0answers
65 views

Parallel Kernel Status

For parallel computing, the window Parallel Kernel Status shows some information on the subkernels. I can use two kernels, and which each of them I can do parallel computations. However, it seems that ...
2
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0answers
94 views

ParallelTable kernels die - maybe Mathlink timeout?

I am new to parallel computing in Mathematica. I am using LaunchKernels[16] ParallelTable[] to parallelize calculations. The ParallelTable consists of approx ...
2
votes
0answers
33 views

do successive parallel computations require distribute definitions at each intermediate step?

Suppose I am doing a parallel computation, say, using parallel table. I distribute necessary definitions to all kernels. After computation is done, I would like to use the first result in another ...
2
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0answers
250 views

ParallelSum in Mathematica 9 vs 10

Here's part of a package I'm working on: ...
2
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0answers
170 views

Death of parallel sub-kernels

EDIT : Finally, the new Mathematica 10.0 seems to fix it. I have a little parallelization problem. I wrote a code to generate a quasicrystal by dynamical generation. Here the code: ...
2
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0answers
45 views

Timing of ParallelDo versus Do: simple example [duplicate]

I'm trying to understand why a simple do-loop takes substantially longer when done in parallel than sequentially: ...
2
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0answers
101 views

ParallelTable and expensive functions

I would like to build up a 2D-Table using ParallelTable as follows ...
2
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0answers
340 views

Remote kernel shuts down after several seconds

I have Mathematica 9 installed on two Windows Server 2008 R2 machines. Now i want to try using one of them as a frontend with local kernels and the other one for remote kernels. OpenSSH 6.5 for ...
2
votes
0answers
112 views

Whether NIntegrate evaluation is multithreaded or not?

About MultiThread evaluation I am talking about here, see this post I am NIntegrate the function grarm[e, 3, dimension, 1, 1, 0.005]. There is matrix operation in ...
2
votes
0answers
71 views

Setting Up Lightweight Grid On Multiple Clients Programmatically

I have a number of computers which all might need to use the same (client) configuration for the Wolfram Lightweight Grid at some point. I know that there are ways to programmatically set certain ...
2
votes
0answers
91 views

How can you link Parallel Mapping and Error tracking

Following this question and the comments made, together with the information in this question, the following code allows error tracking and debugging very nicely. ...
2
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0answers
133 views

correct usage of ParallelTable

I am trying to parallelize my script. Here is a MWE of how I have done it: ...
2
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1answer
156 views

Mathematica 9.0 problem: ParallelTable with SQLExecute

I have run into the following problem: when I try to run the following code in Mathematica 9 I get SQL connection error on all kernels. The code is: ...
1
vote
3answers
128 views

Where Statement

Is there a "parallel" way to perform these operations? Indices = {} For[i = 1, i <= Length[w], i++, If[w[[i]] < 0, AppendTo[Indices, i]]] Which gives a ...
1
vote
1answer
107 views

Making ReplaceAll faster

I have a list of functions ncalc that is calculated by ...
1
vote
2answers
59 views

Limit the number of processors used by ParallelTable?

By default, ParallelTable will use all the processors available in a PC. Is there a way to set a limit to the number of processors used by ...
1
vote
2answers
63 views

Incomplete Parallel Mapping

I am still struggling on how to nicely handle list operations in Mathematica, and perform simultaneously parallel computation. We consider a tab of the form ...
1
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2answers
543 views

Integration and Parallel Computing in Mathematica

In mathematica, how would I use parallel computing (or paralleltable) to compute the integrals of $x^2$, $x$, $3x$ from $x=0$ to $10$ just like in the first answer of ...
1
vote
1answer
210 views

ParallelTable and DistributeDefinitions

I have a function in the following form: function[...] := With[ {...}, Table[ anotherfunction[i, j, ...], {i, ...}, {j, ...}, ... ] ] If ...
1
vote
1answer
77 views

Why does Mathematica Spawn Additional Dock Icons on OS X?

I've been running a calculation in parallel that requires a rasterize, and doing this requires one to wrap the rasterization with a UsingFrontEnd command (as is ...
1
vote
1answer
301 views

Parallel computation of a system of differential equation

I need to solve a system of differential equations which contains, at minimum, ten thousands of differential equations. Actually, I am trying to solve density matrix equation. It's like something ...
1
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1answer
132 views

ParallelTable of ParametricNDSolve objects fail

There seems to be a problem with ParametricNDSolveValue togeteher with ParallelTable First we create a ParametricNDSolveValue object ...
1
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1answer
231 views

Version differences in Parallelize

I am having a problem which I guess is due to version difference. I have to generate a list of unitary matrices, which I can do easily. However I came to know about ...