Questions tagged [parallelization]
Questions on parallel computing in Mathematica.
216
questions with no upvoted or accepted answers
19
votes
0answers
190 views
Status of all Evaluators?
Since I have 4 cores on my machine I typically have 4 notebooks open each with their own kernel evaluator. I'd like to construct a dynamic pane similar to the parallel kernels status window:
But that ...
14
votes
0answers
531 views
Mathematica HPC on AWS vs. Azure
I am looking for advice on deploying Mathematica for HPC in an on-demand cloud environment. I occasionally have Mathematica projects that require parallel computing and large amounts of RAM. These ...
14
votes
0answers
4k views
Threads vs Cores: How many kernels need to launch in parallel Mathematica?
I have a dual-core intel machine. I would like to test how many parallel local kernels should be launch to get the optimized performance. Knowing that the HyperThreading technology of Intel could run ...
9
votes
0answers
1k 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 ...
8
votes
0answers
377 views
WolframScript never exits (v11 only)
after updating to version 11, I came across a problem with the execution of package files via bash.
The WolframScript program runs the entire code, but frequently it does not exit properly and as a ...
7
votes
0answers
68 views
What's with the weird HoldRest Attribute of ParallelMap?
Bug introduced in 10.0 or earlier and persisting through 11.1
I have noticed some odd behavior of ParallelMap: When the list, that is mapped over, is not inserted ...
7
votes
0answers
145 views
ParallelSubmit executes only on one kernel
I'm trying to use Parallesubmit to run some calculations in parallel, but it looks like all the calculations are evaluated at one kernel. Consider this example:
<...
7
votes
0answers
186 views
Bug: Calling `SetSharedVariable` while kernels are running hangs them up/crashes them
Bug introduced in 9.0 or earlier and persisting through 11.0.1 or later
Start a fresh kernel Quit, and maybe launch ...
7
votes
0answers
502 views
How to force the compilation language to be C++ (not C) in CreateExecutable or CreateLibrary
I'm trying to speed up a section of a Mathematica 9.0.1 notebook by performing some calculations in C++ with the Cilk Plus and Threading Building Blocks tools available for the Intel C++ 14.0 compiler ...
6
votes
0answers
567 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:
...
6
votes
0answers
533 views
Parallelizing is much slower than single kernel evaluation?
Starting with a vector of matrices, tVec, I would like to parallelize the multiplication of each element with the same matrix ...
5
votes
0answers
126 views
Optimize Use of PeakDetect in Mathematica
I am quite new to Mathematica and I am looking for some advice in order to improve and optimize my code.
Here is what I am trying to do:
Open a stream
Read the stream line by line and store it in "...
5
votes
0answers
89 views
Random number generation within Compile and Parallelization->True
According to this thread RandomChoice is a compilable function.
I use it to generate random numbers in a compiled function with parallelization enabled.
I wrote ...
5
votes
0answers
37 views
Efficient Parallelization of PermutationReplace
I am generating the orbit of a partition of a set of size $n$ under the action of the symmetric group $S_n$. PermutationReplace won't allow itself to be parallelized. Why is this ? Is it because the ...
5
votes
0answers
460 views
Can't Launch Kernels, Updating from Wolfram Research Server
So, I'm running Mathematica on an HPC cluster using the math module command line interface. I'm trying to figure out some problems with attempting to parallelize my ...
5
votes
0answers
115 views
Is there a clean way to parallelize multi-index tables?
The documentation of ParallelTable indicates that if you want to parallelize the evaluation of a table of more than one dimension, such as
...
5
votes
0answers
207 views
ParallelTable slow down, Region functions
I am experiencing speed issues with ParallelTable. There are a few related problems on SX posted here and here, but no resolution. The various respondents to those ...
5
votes
0answers
156 views
Improving the speed of an optimization algorithm via compilation and parallellization
I have written an implementation of eight variants of the PSO-algorithm and I want to test them over a set of test functions. I am using parallelization as it improves the speed a lot and I have also, ...
5
votes
0answers
82 views
The change of precision doesn't work in ParallelDo. Is it a bug in Parallel?
Cross-post: http://zhidao.baidu.com/question/2075301703219376588.html
Input:
...
5
votes
0answers
395 views
Mathematica + RasPi + Parallela = Kaboom?
Is it possible to use the Parallela computing platform to enhance Mathematica computing on a Raspberry Pi?
It's not at all clear to me how to interface the two boards (here it says it's done via ...
5
votes
0answers
209 views
Raster with ColorFunction is blank when Dynamic Updating is disabled
UPDATE
Today I was having these WaveletScalogram problems again. I think this is ultimately some kind of interaction issue with Dynamic. I have narrowed it down to ...
4
votes
0answers
50 views
Is there something wrong with DistributeDefinitions?
I have the following code, which fails to distribute the DownValues for the symbol f. Could anybody please explain what is wrong.
...
4
votes
0answers
31 views
Difference in computation speed of Eigensystem not to expectation for ParallelTable and Table
I was trying to compute the time it takes for Eigensystem to evaluate while being inside a ParallelTable, as it is well-known LAPACK subroutine has an inbuilt Parallelization to it. And the difference ...
4
votes
0answers
96 views
How to do parallel computation when using LinearProgramming function?
I have a LP problem which contains 2n+3 variables with 4n+6 inequality constraints. I was trying to use Mathematica's LinearProgramming function. When n is small, like less than 30, it gives outcome ...
4
votes
0answers
107 views
How to speed up code in ParallelDo loops?
I have a piece of code that I'm trying to run in a ParallelDo over 32 kernels. Using a normal Do loop in a kernel Mathematica ...
4
votes
0answers
820 views
Get::noopen: Cannot open CloudObjectLoader` error when running Mathematica on remote cluster
I have been running Mathematica on a remote cluster for quite sometime. Recently, any jobs that call LaunchKernels[] for parallelization return the error
Get::...
4
votes
0answers
97 views
Parallelize Dateset query
I would like to evaluate a Dataset query in parallel, my latest approach being:
...
4
votes
0answers
111 views
Problem with Parallelization when using Packages
I tried to find a solution to my problem in several answers posted in MSE but due to lack of my knowledge on parallelization territory, I couldn't figure out solution to my problem.
I have a big code ...
4
votes
0answers
384 views
Parallel Kernels and Hyperthreading
I am using Eigenvalues a large number of times on a machine with 8 cores. When I run Eigenvalues one time without any parallel ...
4
votes
0answers
145 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 ...
4
votes
0answers
542 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 ...
4
votes
0answers
761 views
OpenCL vs. CUDA with Mathematica
I am thinking about using GPU programming with Mathematica using a MacBook Pro with a NVIDIA GPU. At this page, the Mathematica documentation says "Programming OpenCL in the Wolfram Language is simple ...
4
votes
0answers
173 views
ParallelTable and expensive functions
I would like to build up a 2D-Table using ParallelTable as follows
...
4
votes
0answers
173 views
LibraryLink parallel performance
I'm trying to use a LibraryLink function in parallel. It is an embarrassingly parallel problem, so that no dependency between those parallel tasks. However I can only get the parallel efficiency about ...
4
votes
0answers
988 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 ...
4
votes
0answers
276 views
4
votes
0answers
214 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.
...
4
votes
0answers
372 views
Mathlink and multithreading
In order to make my computations faster I have developed a C/C++ application calling Mathematica kernel and performing many operations using Mathematica functions for equation solving.
Now I want to ...
3
votes
0answers
50 views
Parallelize import of many files
I'm trying to speed up the import of a large number of files, using ParallelTable to store them in a indexed variable, eqDump. The files are in the folder "Frames" and are named "Conf_Run.1000", "...
3
votes
0answers
42 views
Bags don't work in parallel code?
Appending to a list in parallel works:
b = {};
SetSharedVariable[b]
WaitAll[Table[ParallelSubmit[{p}, AppendTo[b, 1]], {p, 3}]];
(* b is now {1,1,1} *)
But ...
3
votes
0answers
41 views
ParallelDo and Reap/Sow in combination fails
I just realized the following problem. I tried to speed up a program that reads hundreds of files each of size up to 200+ MB and processes them, therefore I changed a ...
3
votes
0answers
101 views
Parallel evaluation of RandomVariate for an InterpolatingFunction
I need to generate a lot of point according to a given distribution. I don't have an analytic form of this distribution so I am using an InterpolatingFunction of ~100 points computed numerically. I ...
3
votes
0answers
126 views
Privilege violation for file or directory
hopefully somebody can help me out with the following;
I have a mathematica .wl script which uses ParallelTable;
When I run this locally (laptop) it works perfectly....
3
votes
0answers
54 views
How can I prevent ParallelTable[] from freezing?
I have spent some time trying to figure this out.
I have a function that appears to be the reason my program is freezing. I am using both MemoryConstrained[] and <...
3
votes
0answers
49 views
Getting a Stack Trace on parallel execution
I find debugging very difficult in Mathematica, perhaps because I am unfamiliar with the appropriate tools. Ideally, I would like a "break on error" like Matlab with step control, however for the ...
3
votes
0answers
90 views
Language`ExpressionStore and ParallelMap
Is there a way to access NewExpressionStore from within a parallelized calculation? I have tried variations of
...
3
votes
0answers
90 views
Too many scheduled tasks (with parallelization)
I have a program that makes many http requests (gathering data from APIs), and computes on that data. Speed is a priority and using the most up to date data in the computations is a priority. ...
3
votes
0answers
57 views
Circumvent DistributeDefinitions
I have a code in which I create a few very large matrices with which I need to do long calculations. I have parallelised my code and, in the end, the thing that slows me the most is the time it takes ...
3
votes
0answers
61 views
ParallelDo with NotebookDirectory[]
I have a main directory with subdirectories numbered (1, 2, 3, ...). In each folder there is an exe file. I execute this code:
...
3
votes
0answers
66 views
“ParallelDo” does not calculate the function well
Now, I'm solving utility maximization problem.
...
