Robert, Can you confirm what CPU is running on that node? The Librato guys have apparently narrowed it down to only happening on the Intel E5507. See this blog post for more:
https://silverline.librato.com/blog/main/EC2_Users_Should_be_Cautious_When_Booting_Ubuntu_10_04_AMIs I checked one of our problem nodes that's still up and sure enough, it's running on an E5507. We have another node using the same CPU but with the same test kernel that was posted by Stefan above. So far, it looks ok, but we haven't put too much load on it yet and it's only been about 4 days. -- You received this bug notification because you are a member of Ubuntu Bugs, which is a direct subscriber. https://bugs.launchpad.net/bugs/708920 Title: Strange 'fork/clone' blocking behavior under high cpu usage on EC2 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
