Questions tagged [parallelization]
Questions on parallel computing in Mathematica.
196 questions
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Why won't Parallelize speed up my code?
What reasons are there that can cause parallelized Mathematica code not to run with full performance?
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Transferring a large amount of data in parallel calculations
Bug fixed in version 11.1
Functions like MemberQ, FreeQ, etc. no longer unpack. Yay!
This question is inspired by one of @...
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How to collect result continuously (interruptible calculation) when running parallel calculations?
This is the most common pattern to compute a table of results:
Table[function[p], {p, parameters}]
(regardless of how it's implemented, it could be a ...
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Are built-in Mathematica functions already parallelized?
I've been noticing something strange since updating to Mathematica 8, and that is that occaisionally I'll see that the MathKernel is using up to 800% CPU in my Activity Monitor on OS X (I have 8 cores)...
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ParallelTable and Table do not give same result
I have a question regarding the use of Parallelize.
In the help one can read that “Parallelize[Table[expr,iter, …]] (which is ...
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Reap, Sow with Parallelize: bad performance, why?
I have a question about the performance of Reap and Sow with Parallelize. I am aware of the following questions
How to collect result continuously (interruptible calculation) when running parallel ...
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3
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Monitor doesn't work with ParallelTable
I can't monitor ParallelTable:
Monitor[ParallelTable[Pause[3]; i, {i, 1, 10}], i]
just displays i until it is finished.
Do ...
- 2,002
8
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1
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Register "initialization code" to run on any newly started parallel kernel
Is it possible to register a some "initialization code" to be run on any newly started parallel kernel?
This would be similar to how ParallelNeeds registers a ...
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45
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Is it possible to speed up ContourPlot on multi-core machines?
It is not very difficult to face a function for which ContourPlot works too slow. And it seems natural that this function can be parallelized well. Anyway, naive <...
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Why is this parallel evaluation with Dispatch[] so slow?
Can you efficiently parallelize this? The parallel versions are much slower than the sequential version, and I'm not sure why. Does SetSharedVariable allow ...
- 2,373
64
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4
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Speeding up this fractal-generating code
I used the code below (which is a sample from this gist containing more similar code) in my answer to my own question about Mandelbrot-like sets for functions other than the simple quadratic on Math....
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48
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Parallelize evaluation of function with memoization
I have a complicated function that I need multiple times, so I want to memoize it and have the first evaluation done in parallel. Unlike in my example below it's not a continuous function, so ...
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Mma 10: Half the parallel power (Macs)?
Here is a comparison of the parallel kernels launched under Mathematica under v9 and v10, on the same identical current 2014 R2-D2 Mac Pro ...
[ Update: Valerio has commented that the same issue ...
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Does Mathematica take advantage of hyper-threading (if it is available)?
I do not know much about computer architecture, but some Intel processors have hyper-threading technology, which can apparently improve parallelization for applications that take advantage of it. In ...
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17
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Package found with `Needs`, but not with `ParallelNeeds`
I want to use a self-written package in a parallel computation. However while Needs["mypackage`"] works without problems, ...
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