Randomly crashing Ubuntu 10.04 on multiple Xen VPS host instances

view full story

http://serverfault.com – So we have Ubuntu 10.04 running - all 64 bit. Kernel 2.6.36 and 2.6.38-15 are having the same issues. Problem is random VPS servers are hanging. We have about 30 instances with this particular host. It freezes with nothing in the logs - neither in dmesg, kernel.log, syslog or anywhere. Logging is configured correctly. However in the console there are multiple "task hung for 120 second" errors during this crash. The system apparently cannot write during this crash. We have two types of servers, Java webapp servers and MySQL servers. Both types are having errors ""task flush-2**/java/kjo (HowTos)