Exception when I make more than 1000 connections to the nettey server

[srikanthlives]

Hi,

I am new user to Netty. I have took Netty and wrote a simple discard server
over Netty. I tried connecting to Netty from a flooding client which make
several connections to the server. I started with 100 connections and it
worked well. than increased it to 1000 connections it increased well.
Finally I increased it to 2000 connections and the server trowed an
exception. 

Server Operating System is : RedHat Linux enterprise 4.

I configured the server settings according to the article
http://www.metabrew.com/article/a-million-user-comet-application-with-mochiweb-part-1

below are the settings taken from the above url
=====================================
# General gigabit tuning:
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 65536 16777216
net.ipv4.tcp_syncookies = 1
# this gives the kernel more memory for tcp
# which you need with many (100k+) open socket connections
net.ipv4.tcp_mem = 50576   64768   98152
net.core.netdev_max_backlog = 2500
# I was also masquerading the port comet was on, you might not need this
net.ipv4.netfilter.ip_conntrack_max = 1048576

Put these in /etc/sysctl.conf then run sysctl -p to apply them. No need to
reboot, now your kernel should be able to handle a lot more open
connections, yay.
==============================================================

==============================================================
Each connection we make requires an ephemeral port, and thus a file
descriptor, and by default this is limited to 1024. To avoid the Too many
open files problem you’ll need to modify the ulimit for your shell. This can
be changed in /etc/security/limits.conf, but requires a logout/login. For
now you can just sudo and modify the current shell (su back to your
non-priv’ed user after calling ulimit if you don’t want to run as root):

$ sudo bash
# ulimit -n 999999
# erl

You might as well increase the ephemeral port range to the maximum too:
# echo "1024 65535" > /proc/sys/net/ipv4/ip_local_port_range
=============================================


First it was throwing too many connections exception at OS level and I
increased the "ulimt" on linux to 999999

Now its throwing a different exception 
=============================
ZoneInfo: /usr/java/jdk1.6.0_16/jre/lib/zi/ZoneInfoMappings (Too many open
files)
ZoneInfo: /usr/java/jdk1.6.0_16/jre/lib/zi/ZoneInfoMappings (Too many open
files)
Exception in thread "pool-1-thread-1" java.lang.InternalError
	at sun.misc.URLClassPath$JarLoader.getResource(URLClassPath.java:752)
	at sun.misc.URLClassPath.getResource(URLClassPath.java:168)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:192)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
	at sun.misc.Launcher$ExtClassLoader.findClass(Launcher.java:229)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:300)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
	at
java.util.ResourceBundle$RBClassLoader.loadClass(ResourceBundle.java:445)
	at java.util.ResourceBundle$Control.newBundle(ResourceBundle.java:2383)
	at java.util.ResourceBundle.loadBundle(ResourceBundle.java:1406)
	at java.util.ResourceBundle.findBundle(ResourceBundle.java:1365)
	at java.util.ResourceBundle.findBundle(ResourceBundle.java:1292)
	at java.util.ResourceBundle.getBundleImpl(ResourceBundle.java:1234)
	at java.util.ResourceBundle.getBundle(ResourceBundle.java:715)
	at java.util.logging.Level.getLocalizedName(Level.java:223)
	at java.util.logging.SimpleFormatter.format(SimpleFormatter.java:64)
	at java.util.logging.StreamHandler.publish(StreamHandler.java:179)
	at java.util.logging.ConsoleHandler.publish(ConsoleHandler.java:88)
	at java.util.logging.Logger.log(Logger.java:458)
	at java.util.logging.Logger.doLog(Logger.java:480)
	at java.util.logging.Logger.logp(Logger.java:680)
	at org.jboss.netty.logging.JdkLogger.warn(JdkLogger.java:86)
	at
org.jboss.netty.logging.InternalLoggerFactory$1.warn(InternalLoggerFactory.java:133)
	at
org.jboss.netty.channel.socket.nio.NioServerSocketPipelineSink$Boss.run(NioServerSocketPipelineSink.java:242)
	at
org.jboss.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:108)
	at
org.jboss.netty.util.internal.IoWorkerRunnable.run(IoWorkerRunnable.java:46)
	at
java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	at java.lang.Thread.run(Thread.java:619)
Caused by: java.util.zip.ZipException: error in opening zip file
	at java.util.zip.ZipFile.open(Native Method)
	at java.util.zip.ZipFile.<init>(ZipFile.java:114)
	at java.util.jar.JarFile.<init>(JarFile.java:133)
	at java.util.jar.JarFile.<init>(JarFile.java:70)
	at sun.misc.URLClassPath$JarLoader.getJarFile(URLClassPath.java:643)
	at sun.misc.URLClassPath$JarLoader.access$600(URLClassPath.java:538)
	at sun.misc.URLClassPath$JarLoader$1.run(URLClassPath.java:605)
	at java.security.AccessController.doPrivileged(Native Method)
	at sun.misc.URLClassPath$JarLoader.ensureOpen(URLClassPath.java:597)
	at sun.misc.URLClassPath$JarLoader.getResource(URLClassPath.java:750)
	... 31 more


Can some one help? 

FYI: I am running the program from discard server from eclipse.

Regards,
Srikanth

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