The Wiert Corner – irregular stream of stuff

Jeroen W. Pluimers on .NET, C#, Delphi, databases, and personal interests

  • My work

  • My badges

  • Twitter Updates

  • My Flickr Stream

  • Pages

  • All categories

  • Enter your email address to subscribe to this blog and receive notifications of new posts by email.

    Join 1,346 other followers

Archive for February 13th, 2018

Some useful commands for Proxmox high IO troubleshooting

Posted by jpluimers on 2018/02/13

After trying to move an operating system from one disk to another, Proxmox stalled the console and ended up in a really high I/O delay.

These commands helped me finding out what was wrong:

apt-get install iotop
iotop
ps -aux | grep usbbackup
ps -aux | grep rsync
zpool status
lvscan
qm list
qm unlock ###
qm stop ###

Somehow Proxmox was thinking the VM ### was still in use, but on Linux level it wasn’t:

# lvscan
ACTIVE '/dev/pve/swap' [8.00 GiB] inherit
ACTIVE '/dev/pve/root' [27.75 GiB] inherit
ACTIVE '/dev/pve/data' [62.04 GiB] inherit
ACTIVE '/dev/pve/vm-###-disk-1' [40.00 GiB] inherita

–jeroen

Posted in *nix, Power User, Proxmox, Virtualization | Leave a Comment »

Always watch your uA sources: The mystery of the Zombie RAM | josh.com

Posted by jpluimers on 2018/02/13

Interesting read [WayBack]: The mystery of the Zombie RAM | josh.com that starts with

It all started one bright morning when I wondered: Can the RAM memory on an AVR chip continue to store data after power is removed? If it can hold the data even just for a brief moment, then…

TL;DR: Always watch your uA sources. Or like Lübbe Onken puts it on G+:

In my first company, we had built a piece of hardware, which turned itself on mysteriously sometimes. We found out that this was caused by a status led that created enough current in bright sunlight.

–jeroen

via:

 

Posted in Arduino, Development, Hardware Development | Leave a Comment »

 
%d bloggers like this: