Chris Kirk kirkch

kirkch / gist:5211438

Last active December 15, 2015 05:49

Useful JVM Settings (Oracle VM)


	Native Compilation Options
	-----------------------

	XX:+PrintCompilation Prints out when HotSpot stops the world to compile a method into native code
	-XX:CompileThreshold=1000 Sets the number of invocations required before a method will be considered for compilation.
	Trades off startup time and resources for speed. -client sets this to 1500, -server runs with 10,000

kirkch / gzip all files

Created February 9, 2013 16:05

gzip multiple files individually

find . -maxdepth 1 -type f ! -name `*.gz` -exec gzip "{}" \;

kirkch / gist:3450993

Created August 24, 2012 14:07

Changing ulimit on Ubuntu

	Verification
	Check your system limits:

	$ cat /proc/sys/fs/file-max
	$ sysctl -a \|grep fs.file-max


	To check the number of file descriptors used by any given process use

	$ ls -la /proc/<pid>/fd

kirkch / gist:3427722

Created August 22, 2012 17:23

rsync notes

	-- RSync server config ( /etc/zeebox/rsync.conf

	lock file = /var/run/rsync.lock
	log file = /var/log/rsyncd.log
	pid file = /var/run/rsyncd.pid

	[cache]
	path = /mnt/cache
	uid = tomcat
	gid = tomcat

kirkch / gist:3427668

Created August 22, 2012 17:15

Expanding jar files in a directory on to a Java Classpath


	Use this when the Java 5 dir/* syntax does not work. This hit me using Gatling on Ubuntu recently.

	CLASSPATH="$(echo $GATLING_HOME/lib/*.jar \| tr ' ' ':'):$GATLING_CONF:${JAVA_CLASSPATH}"

kirkch / gist:3402882

Created August 20, 2012 10:19

Fast ways of writing to disk in Java


	import java.io.*;
	import java.nio.*;
	import java.nio.channels.*;

	/**
	* Compares the performance of streaming data to disk vs using memory mapped files.
	*.
	public class MappedIO {
	private static int numOfInts = 4000000;

kirkch / ProxifierPerformance.java

Created July 31, 2012 06:35 — forked from garcia-jj/ProxifierPerformance.java

cglib vs javassist performance tests

	package com.mosaic.esa;

	import javassist.util.proxy.MethodHandler;
	import javassist.util.proxy.ProxyFactory;
	import javassist.util.proxy.ProxyObject;
	import net.sf.cglib.proxy.Enhancer;
	import net.sf.cglib.proxy.MethodInterceptor;
	import net.sf.cglib.proxy.MethodProxy;
	import org.junit.Test;