[erlang-questions] Erlang C-nodes crashed randomly with double free, memory corruption malloc messege

[Sverker Eriksson]

Have you tried to run your c-node under valgrind.

http://valgrind.org/.


/Sverker


On 11/15/2016 08:32 PM, Silver Surfer wrote:
> Hi,
> I have an application running on otp-19.0, where there is a single erlang
> node and two c-nodes; several processes from erlang node continuously send
> messages to the c-node servers. The c-node accepts a single connection and
> process all the received messages (ERL_MSG-> ERL_REG_SEND, ERL_SEND) in
> separate threads except ERL_TICK, ERL_ERROR etc.
>
> So in the c-node main() a connection is accepted and all the messages are
> received (erl_receive_msg), if the message is ERL_TICK, ERL_ERROR etc. they
> are dealt appropriately by freeing the memory, else if the message is
> ERL_MSG then a thread is created and the message is passed to the thread
> where it is processed and a reply is send using erl_send; this approach of
> handling message through thread is taken as some of the operation performed
> by the c-node takes considerable amount of time which is more than the tick
> time (is there a better way to do this?).
>
> Now out of the two c-nodes one is crashing randomly (10 times in 24Hrs,
> more or less); both the c-nodes follows same architecture, only the
> operations they perform are different. In most of the times the c-node just
> goes down without giving any error reason and in 2 or 3 cases it crashes
> because of double free or memory corruption printer by malloc, the trace
> back points to erl_receive_msg.
>
> Another point observed is that, in the thread after erl_free_compound, when
> we look at the allocated blocks using erl_eterm_statistics(allocated,
> freed), it is 0 most of the times but sometimes it is non zero value, i.e.
> 9, 18, etc.
>
> Any help is appreciated.
>
> Greg
>
>