I tried to run BSP job using netty-based RPC instead of message bundle, but I received "too many open files".
-- attempt_201504280858_0001_000017_0: 15/04/28 08:28:17 INFO ipc.AsyncClient: AsyncClient startup attempt_201504280858_0001_000017_0: 15/04/28 08:28:21 ERROR bsp.BSPTask: Error running bsp setup and bsp function. attempt_201504280858_0001_000017_0: java.lang.IllegalStateException: failed to create a child event loop attempt_201504280858_0001_000017_0: at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:68) attempt_201504280858_0001_000017_0: at io.netty.channel.MultithreadEventLoopGroup.<init>(MultithreadEventLoopGroup.java:49) attempt_201504280858_0001_000017_0: at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:61) attempt_201504280858_0001_000017_0: at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:52) attempt_201504280858_0001_000017_0: at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:44) attempt_201504280858_0001_000017_0: at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:36) attempt_201504280858_0001_000017_0: at org.apache.hama.ipc.AsyncClient$Connection.<init>(AsyncClient.java:189) attempt_201504280858_0001_000017_0: at org.apache.hama.ipc.AsyncClient.getConnection(AsyncClient.java:989) attempt_201504280858_0001_000017_0: at org.apache.hama.ipc.AsyncClient.call(AsyncClient.java:838) attempt_201504280858_0001_000017_0: at org.apache.hama.ipc.AsyncRPC$Invoker.invoke(AsyncRPC.java:261) attempt_201504280858_0001_000017_0: at com.sun.proxy.$Proxy14.getProtocolVersion(Unknown Source) attempt_201504280858_0001_000017_0: at org.apache.hama.ipc.AsyncRPC.checkVersion(AsyncRPC.java:524) attempt_201504280858_0001_000017_0: at org.apache.hama.ipc.AsyncRPC.getProxy(AsyncRPC.java:509) attempt_201504280858_0001_000017_0: at org.apache.hama.ipc.AsyncRPC.getProxy(AsyncRPC.java:477) attempt_201504280858_0001_000017_0: at org.apache.hama.ipc.AsyncRPC.getProxy(AsyncRPC.java:435) attempt_201504280858_0001_000017_0: at org.apache.hama.ipc.AsyncRPC.getProxy(AsyncRPC.java:545) attempt_201504280858_0001_000017_0: at org.apache.hama.bsp.message.HamaAsyncMessageManagerImpl.getBSPPeerConnection(HamaAsyncMessageManagerImpl.java:155) attempt_201504280858_0001_000017_0: at org.apache.hama.bsp.message.HamaAsyncMessageManagerImpl.transfer(HamaAsyncMessageManagerImpl.java:203) attempt_201504280858_0001_000017_0: at org.apache.hama.bsp.BSPPeerImpl.sendDirectly(BSPPeerImpl.java:382) attempt_201504280858_0001_000017_0: at org.apache.hama.bsp.BSPPeerImpl.send(BSPPeerImpl.java:364) attempt_201504280858_0001_000017_0: at org.apache.hama.graph.GraphJobRunner.loadVertices(GraphJobRunner.java:467) attempt_201504280858_0001_000017_0: at org.apache.hama.graph.GraphJobRunner.setup(GraphJobRunner.java:128) attempt_201504280858_0001_000017_0: at org.apache.hama.bsp.BSPTask.runBSP(BSPTask.java:170) attempt_201504280858_0001_000017_0: at org.apache.hama.bsp.BSPTask.run(BSPTask.java:144) attempt_201504280858_0001_000017_0: at org.apache.hama.bsp.GroomServer$BSPPeerChild.main(GroomServer.java:1255) attempt_201504280858_0001_000017_0: Caused by: io.netty.channel.ChannelException: failed to open a new selector attempt_201504280858_0001_000017_0: at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:128) attempt_201504280858_0001_000017_0: at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:120) attempt_201504280858_0001_000017_0: at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:87) attempt_201504280858_0001_000017_0: at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:64) attempt_201504280858_0001_000017_0: ... 24 more attempt_201504280858_0001_000017_0: Caused by: java.io.IOException: Too many open files attempt_201504280858_0001_000017_0: at sun.nio.ch.IOUtil.makePipe(Native Method) attempt_201504280858_0001_000017_0: at sun.nio.ch.EPollSelectorImpl.<init>(EPollSelectorImpl.java:65) attempt_201504280858_0001_000017_0: at sun.nio.ch.EPollSelectorProvider.openSelector(EPollSelectorProvider.java:36) attempt_201504280858_0001_000017_0: at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:126) attempt_201504280858_0001_000017_0: ... 27 more attempt_201504280858_0001_000017_0: 15/04/28 08:28:21 INFO ipc.AsyncServer: AsyncServer gracefully shutdown -- Best Regards, Edward J. Yoon
