# Kernel crash after idle in version 10.0

Bug introduced in 10.0.0 and fixed in 10.0.2

In version 10.0, when I leave the Mathematica section idle for some time (of order an hour), the kernel quit automatically. The syntax highlighting is gone and the variables that has defined before lost their values. There is no error message (tried to launch from terminal and still no error message).

This behavior has been noticed on my computer for many times. No operation is performed. Simply launch Mathematica 10 and wait (or define a variable and watch it gone). Mathematica 9 is installed side by side and has no such problem. I am using Linux (CentOS 7).

Anyone has the same problem, or any suggestions to further debug?

\$Version


10.0 for Linux x86 (64-bit) (June 29, 2014)

uname -a


Linux localhost.localdomain 3.10.0-123.el7.x86_64 #1 SMP Mon Jun 30 12:09:22 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux

Update:

I unchecked Preference -> Internet Conectivity -> Allow the Wolfram System to access the Internet. The kernel hasn't crashed since this change is made.

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I got something similar, although I haven't noticed that I particularly left Mathematica alone. I just noticed that my kernel has crashed after a while. I'm trying now to leave it idle. My OS is Ubuntu 12.04. – halirutan Jul 13 '14 at 23:55
This is at least the third different crash report of version 10 here in the last 8 hours alone. I think I'll postpone my upgrade until 10.1 :-( – stevenvh Jul 14 '14 at 10:16
Is this observed on any other OS? – rcollyer Jul 14 '14 at 12:33
My Mathematica 10 has been on for over 3 days now. I don't have this problem on Windows 8.1 – RunnyKine Jul 14 '14 at 13:12
I've been having this same problem (but only after a few minutes idle time) with Mathematica 10.0 on Mac OS X 10.9.4. I had contacted Wolfram Support but it's being investigated. I will try the workaround! – José Figueroa-O'Farrill Aug 13 '14 at 23:07

To upgrade my comment to an answer, and perhaps give some more background information:

This bug has been fixed as of version 10.0.2. The crash happened in the libcurl library, which is being used in a separate thread via the HTTPClient package by the paclet manager at kernel startup to check for updates. It had to do with thread safety in certain circumstances, namely a DNS resolver thread taking too long to complete its task. It is essentially the same problem described here or here.

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Can you check if this is a bug, or a misunderstanding of how the functions should be used, please? – Szabolcs Aug 31 '15 at 22:20
@Szabolcs It does feel like a bug, though this is not my area. I forwarded your post to the people who have implemented that functionality. – ilian Sep 1 '15 at 18:17

Now that the workaround has worked for me for days without crash, let me put it as an answer myself. The crash (at least in my case) is because of the kernel tries to connect to internet and something wrong happened there. To solve the problem, uncheck

Preference -> Internet Conectivity -> Allow the Wolfram System to access the Internet

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amazing bug. Kernel crashes because it can't connect to the internet ! – Nasser Jul 16 '14 at 6:43
I saw a similar issue when I tried some geodata stuff on a ferry with extremely congested satellite link and a transparent HTTP proxy. I wasn't able to reproduce the issue, but it certainly seemed like an issue with network connectivity. – kirma Jul 18 '14 at 6:56