Too many open files

[jnehring]

FREME live becomes unstable after running for a while with this error:

ERROR   2016-04-26 08:42:24,909 [http-nio-8004-Acceptor-0] org.apache.tomcat.util.net.NioEndpoint  - Socket accept failed
java.io.IOException: Zu viele offene Dateien
        at sun.nio.ch.ServerSocketChannelImpl.accept0(Native Method)
        at sun.nio.ch.ServerSocketChannelImpl.accept(ServerSocketChannelImpl.java:422)
        at sun.nio.ch.ServerSocketChannelImpl.accept(ServerSocketChannelImpl.java:250)
        at org.apache.tomcat.util.net.NioEndpoint$Acceptor.run(NioEndpoint.java:686)
        at java.lang.Thread.run(Thread.java:745)

It happened two weeks ago and now it happened again. The problem can be solved through restarting freme-live.

I backuped the log files (around 500 mb or error logs) in ~/logs-open-files on freme-live. I guess the problem is an open file handle or stream that is not closed properly. When this happened 20.000 times then freme-live fails. Probably it is caused by the WRIPL requests because no one else does so many requests in two weeks on freme-live.

[jnehring]

The bug happend again. We should fix it soon.

[jnehring]

I can test the issue by starting FREME on ubuntu and using this command to count the number of open file handles:

lsof -a -p 3919 | wc -l

where 3919 is the process id of freme.

The number of file handles increases with each API call that uses e-Internationalisation. I could find and fix two streams that where not closed properly and reduce the number of newly opened streams by each API call from 3 to 1.

Next step: Find the last stream that is not closed properly.

[ArneBinder]

This hould be fixed. @jnehring could you check this on freme-dev?
This does not solve freme-project/basic-services#32.

[jnehring]

I tested it. The problem is fixed. Great!

[jnehring]

The bug happened again today.