Your 2 linked tasks: The first one was too late but on time before your resend turned in. The second task may have restarted task's VM several times maybe starting from scratch.


Both tasks are still running and it's not clear whether:
- the first task, which already had a valid result, will grant me credits if I finish it?
- if I won't finish the second task in 11 days, will it get cancelled and will I lose all 11 days of running time? If a third replicate gets sent out after 10 days I don't think anyone will finish it within 24 hours (before my hard deadline) so that shouldn't be an issue.

Edit: after re-reading your reply several times I think I figured out the misunderstanding. In both WUs that I linked, I'm running the resends, not the initial tasks.

Then I read your comment (thank you very much) and explored "Show graphics" command and beyond at BOINC Manager.
When selecting a running Theory task, command "Show graphics" gets enabled.
When pressing "Show graphics", an explorer window opens, containing a link to "logs".
If that link is pressed, a very useful "Index of /logs/" page opens.
That page contains a "Last Modified:" label that gives a clue on whether "running.log" file has been recently updated or not.
When updating "running.log" file becomes frozen, it can be taken as a warning to abort the corresponding task.
And if "running.log" is being periodically updated, it can be taken as a signal that the task is still alive.
"Index of /logs/" page also contains a link to "running.log" file itself.
At the beginning of "running.log" file, a definition of the task is shown.
The penultimate parameter on the first line indicates the stated number of events for the task. 55000 in this example.
And at the end of the file, progress of the task can be followed.

Wow, many thanks for the detailed explanation! Can't wait to get home tomorrow and check my two long tasks.

Your computer runs VirtualBox 5.2.20.
The Theory guest runs Linux kernel 5.14.
VirtualBox introduced initial support for kernel 5.14 (host and guest) with version 6.1.28.
https://www.virtualbox.org/wiki/Changelog-6.1

There's no 'obvious error' reported back to the project.
In cases like that there is no log file from the scientific app sent back to the project.
Hence, there is nothing to analyse and the task is either marked as 'failed' or 'lost' after the due date.

Even the log snippets you posted do not clearly explain if/why the tasks got stuck.

So, how should the project decide what caused the failure.
It could be either (may be incomplete):
- hardware
- the OS
- VirtualBox
- BOINC
- vboxwrapper
- data from CVMFS
- scientific app

From the project's perspective there's only the overall task failure rate for the computer itself.
As already mentioned for this computer it is less than 1 % covering all possible reasons.

This is a bug in VirtualBox 7.2.4.

On a computer with AMD CPU there's no known workaround so far.
...
After more testing...
Looks like the downgrade left the 7.2.4 kernel module on the system.
It now works after a cleanup and a fresh 7.2.2 installation (package from VirtualBox).

The kvm_amd module must remain blacklisted.

Hello,

I downloaded the script theory-vbox.sh from link https://github.com/seanr22a/LHC-Theory/blob/main/theory-vbox.sh
Then I tried to run it with the following Terminal command:

sh theory-vbox.sh
And I got the following result:

-e

--- LHC Theory - USER ---- 2025-09-24 16:27:48 ------------------------------------------------------

| Events |
Slot Job id Total Processed Remaining Elapsed time Completed % Err
------------------------------------------------------------------------------------------------------
theory-vbox.sh: 101: Syntax error: word unexpected (expecting ")")
Some kind advice would be very appreciated

... What is it about this project's crunching that produces such wildly varying runtimes?...
It's a result of the scientific input which you get (by random) from the backend queues.
More details can be found here:
http://mcplots-dev.cern.ch/
currently in progress:
http://mcplots-dev.cern.ch/production.php?view=revision&rev=2922