Showing posts from 2015

Reduce TIME_WAIT Socket Connections

Sometime, you’ll run across an Apache server that always has tons of TIME_WAIT connections just seeming to hang out. While these don’t take up as many resources as an ESTABLISHED connection, why keep them around so long? This will show you how to identify how many you have, and how to tell your server to reduce them, reuse and recycle them

Most Useful Java Libraries

Here are most useful Java libraries (third-party libraries) for Java programmer

10 Most Common Java Mistakes

Here are 10 most common Java mistakes

Snippet Redshift

With snippet Redshift, you can free your mind

Snippet Java for Redshift

With snippet Java for Redshift, you can free your mind

Setup HBase

HBase is the Hadoop database, a distributed, scalable, big data store. Use Apache HBase™ when you need random, realtime read/write access to your Big Data. This project's goal is the hosting of very large tables -- billions of rows X millions of columns -- atop clusters of commodity hardware

Compile Hadoop from Source

Compile Hadoop 2.x help you fix error Unable to load native-hadoop library

Apache Gzip Compression

Enable apache gzip compression in you web server can reduces the time it takes for a website to transfer the page files and style sheets which ultimately reduces the load time of your website

Fix ssl_error_weak_server_ephemeral_dh_key Firefox

From Firefox 39, user maybe occur ssl_error_weak_server_ephemeral_dh_key when using HTTPS. This post help fix ssl_error_weak_server_ephemeral_dh_key from tomcat server or ignore this in Firefox by user

Fix Certificate Verify Failed in Ruby

If you install ruby with RubyInstaller, when trying to pull updates from RubyGems, you maybe occur error SSL error certificate verify failed. This post help you fix this issue or upgrades SSL on

Cygwin Connect to MySQL

Can't connect to local MySQL server through socket '/var/run/mysql.sock'

How to Add a Root User on Linux

When you first start using a fresh Linux server, adding and removing users is one of the most basic tasks that you should know how to do. When you create a new server, you are only given the root account by default. While this gives you a lot of power and flexibility, it is also dangerous to regularly use an account with so much power; for example, a root user is more vulnerable to security exploits, since any commands run under that account can affect the server's entire filesystem.

Turn Off Linux Screensaver

It is easy to turn off linux screensaver under X window. But when it comes to text based login or terminal you will not find easy way to disable text based power saving mode (i.e. when your screen goes blank after a few minutes)

Tomcat Gzip Compression

Enable tomcat gzip compression in you application server can improve performance by reducing network load for some resources.

Cygwin Open Bash Prompt Here

Cygwin is a large collection of GNU and Open Source tools which provide functionality similar to a Linux distribution on Windows.

MinGW Open MSYS here

MSYS is a collection of GNU utilities such as bash, make, gawk and grep to allow building of applications and programs which depend on traditionally UNIX tools to be present. It is intended to supplement MinGW and the deficiencies of the cmd shell.

Increase Heap Size in Java

How to fix java.lang.OutOfMemoryError: Java heap space

Show Why Linux Kill Process

Linux overcommits memory

Start Multiple MySQL Instances

Starting Multiple MySQL Instances at the Windows Command Line

12 Benefits of Spring MVC over Struts

Spring is a powerful Java application framework, used in a wide range of Java applications. It provides enterprise services to Plain Old Java Objects (POJOs). Spring uses dependency injection to achieve simplification and increase testability.

Speed Up Eclipse

Speed up eclipse as a super fast IDE

MySQL Query Log

General Query and Slow Query Log

How to Configure Tomcat Always Require HTTPS

Protecting Java EE Web Apps with Secure HTTP Headers

Tomcat Configuration Recommendations

How To Set TimeZone in Java

You can set timezone for many common programs like Java or MySQL server. And of course you can do it with JVM. JVM Host clients can set timezone with our custom JVM control panel JVMCP. Timezone can also be set directly in shell variable or as Java command line parameter. Here is how to set timezone in Java

How to Create a Amazon EC2 AMI from Snapshot

If you have Amazon EC2 instances, it might be a good idea to pause and make sure you have a good backup and recovery plan.