Hi, I am using Cassandra 2.0.9 running on Debian Wheezy, and I am having "too many open files" exceptions when I try to perform a large number of operations in my 10 node cluster.
I saw the documentation http://www.datastax.com/documentation/cassandra/2.0/cassandra/troubleshooting/trblshootTooManyFiles_r.html and I have set everything to the recommended settings, but I keep getting the errors. In the documentation it says: "Another, much less likely possibility, is a file descriptor leak in Cassandra. Run lsof -n | grep java to check that the number of file descriptors opened by Java is reasonable and reports the error if the number is greater than a few thousand." I guess it's not the case, or else a lot of people would be complaining about it, but I am not sure what I could do to solve the problem. Any hint about how to solve it? My client is written in python and uses Cassandra Python Driver. Here are the exceptions I am having in the client: [s1log] 2014-08-08 12:16:09,631 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.151, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,632 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.142, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,633 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.143, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,634 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.142, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,634 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.145, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,635 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.144, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,635 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.148, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,732 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.146, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,733 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.77, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,734 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.76, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,734 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.75, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,735 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.142, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,736 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.185, scheduling retry in 600.0 seconds: [Errno 24] Too many open files [s1log] 2014-08-08 12:16:09,942 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.144, scheduling retry in 512.0 seconds: Timed out connecting to 200.200.200.144 [s1log] 2014-08-08 12:16:09,998 - cassandra.pool - WARNING - Error attempting to reconnect to 200.200.200.77, scheduling retry in 512.0 seconds: Timed out connecting to 200.200.200.77 And here is the exception I am having in the server: WARN [Native-Transport-Requests:163] 2014-08-08 14:27:30,499 BatchStatement.java (line 223) Batch of prepared statements for [identification.entity_lookup, identification.entity] is of size 25216, exceeding specified threshold of 5120 by 20096. ERROR [Native-Transport-Requests:150] 2014-08-08 14:27:31,611 ErrorMessage.java (line 222) Unexpected exception during request java.io.IOException: Connection reset by peer at sun.nio.ch.FileDispatcherImpl.read0(Native Method) at sun.nio.ch.SocketDispatcher.read(SocketDispatcher.java:39) at sun.nio.ch.IOUtil.readIntoNativeBuffer(IOUtil.java:223) at sun.nio.ch.IOUtil.read(IOUtil.java:192) at sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:375) at org.jboss.netty.channel.socket.nio.NioWorker.read(NioWorker.java:64) at org.jboss.netty.channel.socket.nio.AbstractNioWorker.process(AbstractNioWorker.java:109) at org.jboss.netty.channel.socket.nio.AbstractNioSelector.run(AbstractNioSelector.java:312) at org.jboss.netty.channel.socket.nio.AbstractNioWorker.run(AbstractNioWorker.java:90) at org.jboss.netty.channel.socket.nio.NioWorker.run(NioWorker.java:178) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Here is the amount of open files before and after I restart Cassandra: root@h:/etc/security/limits.d# lsof -n | grep java | wc -l 936580 root@h:/etc/security/limits.d# sudo service cassandra restart [ ok ] Restarting Cassandra: cassandra. root@h:/etc/security/limits.d# lsof -n | grep java | wc -l 80295 Best regards, Marcelo Valle.
