Play! framework hangs on compile, no errors reported

Question

Just moved my app to a new CentOS server. After fiddling for a long time, I can't play to compile or get any errors. The shell output will show me the last file compiling and then hang. I'm running the Scala 0.9.1 module.

I did a strace on the process, this is all I got. Not sure if it helps.

futex(0x410489d0, FUTEX_WAIT, 5403, NULL

Any ideas to the cause? Or where I can begin troubleshooting?

Thanks.

Answer 1

As it turns out tmbrggmn was right and this is indeed related to the particular kernel on the machine I was using.

The particular kernel was an open source Zen kernel running CentOS and was using software virtualization. I migrated to a Citrix Kernel and now Play! compiles just fine.

A uname -a on the buggy kernel was:

Linux examplehost.com 2.6.18-274.17.1.el5xen #1 SMP Tue Jan 10 18:06:37 EST 2012 x86_64 x86_64 x86_64 GNU/Linux

Answer 2

Googling on FUTEX_WAIT I found this mailing list thread for OpenJDK describing your problem. They advised the user to go to the distro-specific forum and ask the same question, which led me to this forum thread which is specific for Fedora 10. This seems to be a "common" problem related to some Linux distros, some JVMs and gvfs-fuse-daemon or some other process keeping locks.

No idea towards a specific solution, but I hope one of the following helps:

• Read this question which deals with the same issue, only related to Citrix
• This problem seems to have been around a while, so make sure you update your JVM to the latest version
• Update your distro to the latest version if at all possible (especially any kernel updates, which according to this Sun bug fixed the issue)
• Contact the CentOS community as this issue seems to be related to futex and Linux; they should be able to help you further

I didn't immediately come across a clear solution for this issue, so if you find one, please update this question so we can save it for future generations to come ;-)