100
votes
Accepted
Mathematica 10.0.x freezes in Initializing kernels
Yes, there was a recently pushed incorrect paclet update that will cause this startup hang. All platforms can be affected, not just Windows.
For a workaround, start a standalone kernel (...
20
votes
Restarting Mathematica automatically
You could launch a different kernel and use that to run the computation. You will be controlling this "slave kernel" from another Mathematica session. This will allow you to script even quitting and ...
19
votes
Mathematica 10.0.x freezes in Initializing kernels
I'm adding an alternate solution for Mac, as the suggested answer did not work for me. It might be due to me force quitting it prior to looking for a solution.
This method is a bit of a scorched ...
18
votes
Accepted
Quit the Kernel and start new session automatically
This can be relatively easily done using extremely useful $FrontEnd option "ClearEvaluationQueueOnKernelQuit" introduced by ...

Kuba♦
- 135k
18
votes
What secrets are hidden away in your init.m and where do you place it? Please help me build the ideal init.m
I am an init.m ascetic. And I doubt after 30+ years of using Mathematica I will change. Everyone else, who wishes to, may proclaim how it is indispensable to their workflow, and I will accept their ...
Community wiki
17
votes
How to restart computation when kernels die?
One approach would be to run the evaluation in a second kernel which is controlled from a main kernel through MathLink/WSTP. Then your main kernel can detect if the MathLink connection dies.
You can ...
16
votes
Accepted
Detecting kernel initialization
Apparently, Throw is deactivated during kernel initialization. The following function can determine if Throw is inoperative:
<...
14
votes
Detecting kernel initialization
After some spelunking, I found a file which contains a lot of initialization code, including reading the kernel init.m file, loading ...
13
votes
Accepted
Handling Kernel start. What is a full initialization stack and what place the Autoload has there?
Update
Leaving my original answer below for historical purposes, however it only applies up until version 11.1.1.
As of version 11.2.0, the kernel startup initialization has been overhauled and this ...
13
votes
Accepted
How to restart computation when kernels die?
Assuming FrontEnd survives, prepare 3 cells:
...

Kuba♦
- 135k
13
votes
How to use the Autoload directory?
In order for a package in Autoload to load, it must have the file Kernel/init.m. Thus,
...
11
votes
What secrets are hidden away in your init.m and where do you place it? Please help me build the ideal init.m
I tend to put a lot of little functions in my init.m file, functions that take arguments and use module variables. I found that I would now have Global symbols like ...
Community wiki
10
votes
Different strategies to get a clean Kernel. Quit, Exit, ClearAll, Remove, CleanSlate?
PREVENTION
This is a Community Wiki answer, experienced users are welcome to add to it and correct mistakes.
Best practice is to avoid the need to clean the kernel at all, by avoiding the creation ...
9
votes
Restarting Mathematica automatically
On Windows you can run your cycles in a batch file like this:
...
9
votes
Accepted
Parallel computing: cores vs threads
It seems I misunderstood the kind of threading you were addressing when writing my original reply (below). For internally multithreaded functions launched from a single kernel I you can limit the ...
8
votes
Accepted
Serious Startup Error: Error code 583
This error message has occurred before with a corrupted init.m file.
Check your init.m files if you have edited them. Otherwise, the article @JHM linked to you should fix the problem.
8
votes
How to ensure that a package is always loaded on startup, even in parallel kernels?
The Autoload mechanism can be used for this. Place the package in $UserBaseDirectory/Autoload or ...
8
votes
Accepted
Cannot start multiple instances of Mathematica after upgrading to 10.4
WORKAROUND FROM THE TECHNICAL SUPPORT
There are easier ways to perform simultaneous evaluations in Mathematica, with notebooks that remain in separate contexts, all within a single instance of the ...
8
votes
Accepted
How to automatically do a computation, Quit[], restart and do a new computation
You can start a fresh extra kernel programmatically from your current notebook using MathLink. You can then load packages in that kernel, perform necessary calculations, get the result back to your ...
8
votes
Different strategies to get a clean Kernel. Quit, Exit, ClearAll, Remove, CleanSlate?
NEW KERNEL
This is a Community Wiki answer, experienced users are welcome to add to it and correct mistakes.
To get a fresh kernel for the current notebook, one can either kill the current kernel ...
Community wiki
8
votes
Choose the number of kernels used by ParallelTable
Another way from the menu (if accessible): Edit $ \rightarrow $ Preferences $ \rightarrow $ Parallel $ \rightarrow $ Local Kernels $ \rightarrow $ (Number of local kernels to use) Manual setting
7
votes
Accepted
Choose the number of kernels used by ParallelTable
You can launch as many or as few kernels as you like, see LaunchKernels and CloseKernels. Parallel functions will use as many as ...
7
votes
6
votes
Accepted
new kernel for notebook
Ok, so first of all you have to be aware that number of kernels you can use is limited by license.
You can go now to Evaluation -> Kernel Configuration Options ...

Kuba♦
- 135k
6
votes
Accepted
How to avoid kernel shutdown when importing a file
The kernel crash is a bug which arises from deep recursion in string pattern matching. It has been fixed in version 10.1.0 and later, by updating to a more modern version of the PCRE library and ...
6
votes
Accepted
Package loading in init.m
Not all packages can be loaded on startup. There are some operations that simply do not work during startup, the most prominent one being Throw/...
6
votes
Accepted
Kernel starts up very slowly on Linux
I don’t know if the problem you encountered is the same as the problem described in this post. If the same, you need to disable automatic updates.
This failure is caused by the paclet update system. ...
6
votes
5
votes
Kernels permanently consume 100% CPU
OK, issue solved. The problem is apparently caused by a bug in the Linux kernel related to the insertion of a leap second and is only apparent when queried from Java. A solution is given here (...
5
votes
More Information About Solving Mathematica 10.0 Freezing Issue
These are the same steps as in (92931) with a little bit of added detail for Windows.
Make sure any running (or hanging) copies of Mathematica are closed
Navigate to the installation directory, this ...
Only top scored, non community-wiki answers of a minimum length are eligible
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