Decoding Those Inscrutable RCU CPU Stall Warnings
Channel: LinuxConfAu 2018 - Sydney, Australia
Date: 24/01/2018

Paul E. McKenney

http://lca2018.linux.org.au/schedule/presentation/138/

You are minding your own business when suddenly one of your system splats out something like "INFO: rcu_bh_state detected stalls on CPUs/tasks: { 3 5 } (detected by 2, 2502 jiffies)".  Whatever does this RCU CPU stall warning mean and what can you do about it?  That is, other than simply beating your head against Documentation/RCU/stallwarn.txt?

This talk will look at a few representative RCU CPU stall warning messages and show how they can be decoded into real information that can help you find otherwise silent hangs the easy way.  Or at least an easier way!

This talk was given at Linux.conf.au 2018 (LCA2018) which was held on 22-26 January 2018 in Sydney Australia.

linux.conf.au is a conference about the Linux operating system, and all aspects of the thriving ecosystem of Free and Open Source Software that has grown up around it. Run since 1999, in a different Australian or New Zealand city each year, by a team of local volunteers, LCA invites more than 500 people to learn from the people who shape the future of Open Source. For more information on the conference see https://linux.conf.au/

#linux.conf.au #linux #foss #opensource