LHC@home

Getting errors on ATLAS on Windows for the last several hours, for example
https://lhcathome.cern.ch/lhcathome/result.php?resultid=420420649

Log typically shows
2025-03-22 00:47:28 (14472): Adding virtual disk drive to VM. (ATLAS_vbox_3.01_image.vdi)
2025-03-22 00:47:35 (14472): Error in deregister parent vdi for VM: -2135228404
Command:
VBoxManage -q closemedium "D:\ProgramData\BOINC/projects/lhcathome.cern.ch_lhcathome/ATLAS_vbox_3.01_image.vdi"
Output:
VBoxManage.exe: error: Cannot close medium 'D:\ProgramData\BOINC\projects\lhcathome.cern.ch_lhcathome\ATLAS_vbox_3.01_image.vdi' because it has 1 child media
VBoxManage.exe: error: Details: code VBOX_E_OBJECT_IN_USE (0x80bb000c), component MediumWrap, interface IMedium, callee IUnknown
VBoxManage.exe: error: Context: "Close()" at line 1875 of file VBoxManageDisk.cpp

Previous tasks had completed successfully. I've stopped running ATLAS for now. CMS continues to run OK.

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In Virtualbox mediamanager - are there yellow triangles?

In Virtualbox mediamanager - are there yellow triangles?

Under ATLAS_vbox_3.01_image.vdi there is one orphan snapshot entry in slot 11 that has a yellow triangle. The slot has been reused, so the listed error is VERR_PATH_NOT_FOUND.

I don't know how old the orphan entry is. The last two failed ATLAS jobs were in slot 6 and slot 10.

Is the appropriate thing to do to clean up everything ATLAS related and let BOINC download a new copy of the image?

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Your error is caused by a race condition.
Unlike CMS/Theory ATLAS is still using an old vboxwrapper that can't mitigate that race condition.

Needs to be cleaned manually following the steps here:
https://lhcathome.cern.ch/lhcathome/forum_thread.php?id=5982&postid=47976

It is explained for CMS but simply replace CMS_2022_09_07_prod.vdi with ATLAS_vbox_3.01_image.vdi.
Once cleaned up restart ATLAS with 1 running task.
As long as 1 ATLAS task is running (or paused) you can then add as many as you want.

Thanks, that resolved the issue.

The second ATLAS task has started.

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