[erlang-questions] VM silently exits

[Steve Vinoski]

On Wed, Jul 28, 2010 at 10:04 PM, Vinayak Pawar <vinayakapawar@REDACTED> wrote:
>
>> With R13B04 running on Montavista Linux, I've seen a few cases
>> recently where the Erlang VM simply exits without any log messages,
>> crash dumps, or coredumps. It appears to happen only after days of
>> running under load, making it hard to reproduce and investigate. It
>> may be related to memory consumption, but I'm not sure. External
>> programs like heart and memsup simply report "Erlang has closed,"
>> which according to the source code means they each got a return value
>> of 0 from read() on their connection to the VM, which in turn would
>> seem to indicate that the VM side of the connection was simply closed.
>> This would all seem to indicate that the VM was either killed by
>> another process or that it called exit() itself. The Linux "OOM
>> killer" is disabled on this system, and I don't know of any other
>> process that would be killing the VM. There are no alarms in the logs
>> about hitting memory high watermarks or anything like that, and we
>> aren't using any options to change allocators or anything like that.
>>
>> Anybody ever seen anything like this?
>>
> Hi Steve,
>
> Yes, we've noticed this silent exit behaviour of Erlang VM (R13B04) on
> Fedora 12. In our case, about ~12K YAWS/HTTP processes were in contention to
> get lock for compiling same YAWS page. We changed YAWS cache refresh
> interval to some very high figure and got rid of this problem.

Yaws isn't doing that sort of thing in my case, but generally, this is
good info since it's certainly possible some process queue is getting
backed up which of course just worsens over time. We're now running a
periodic check for such things but we haven't caught anything yet
(we're between failures at the moment).

thanks,
--steve