What is SAS and SSD disk

SAS stands for Serial Attached SCSI. 
SAS drive utilizes the same form factor as a SATA drive but has several high performance advantages. While typical SATA drives operate at 7200RPM, a SAS drive operates at 10000RPM or 15000RPM.
SAS drives are typically utilized in server and high-end workstation environments where speed and I/O frequency reign supreme.

SSD stands for Solid State Drive.
Two of SSD can be used in a RAID 0 (Redundant Array of Inexpensive Disks) for the boot and applications drive, but then for scratch disks/additional storage, would be good to have 3-5 or more SAS drives in a RAID 5 (best mix of redundancy and speed, with the addition of parity).

Where stability is concerned, the drives must be properly paired. If drives in a RAID array are not properly matched by Firmware version, the odds are that at least one of the drives will fall out of the array within the first year. Depending on the type of array chosen, this could simply mean the company has to foot the bill for higher hardware costs, or be as bad as catastrophic data loss.

The full post on this topic is here. Read comments as well.

How to restart network service on Mac without reboot

If your network connection got some failure
(for instance VPN does not work) do this command in CML (Terminal):

Choice #1
sudo killall racoon

Choice #2

launchctl stop com.apple.racoon

launchctl start com.apple.racoon

A good one Python Tutorial

Here is the simple and the best Python tutorial I have ever seen.
Won't forget this link )) http://www.tutorialspoint.com/python/index.htm

Matrix effect code in Python

Here is kind of Matrix effect of random numbers running on the screen.
If you know Matrix movie you'll understand what I'm talking about. It is my first and I hope not last try of coding on Python )).

#!/usr/bin/python

import random

start = 11

stop = 99

i = 0

def buildNumberTable(j):

        i = 0;

        list = []

        while i <= j:

                a = random.randrange(start, stop)

                list.append(a)

                i += 1;

        for b in list: print b,

print "\r"

while (i <= stop):

    buildNumberTable(66); #the parameter 66 fits to 15.4" screen if you have 13" put dif. number

    i += 1

    if i == stop:

i=0

How to check TABS and SPACES in NetBeans 7

In order to check Tabs and Spaces in NetBeans 7 do this:

1. Go to View tab on Top Menu.
2. Check Show Non-printable Characters

How to install GWT SDK and SmartGWT on Mac

Install GWT on Mac like this:
1. Download GWT SDK from this site http://code.google.com/intl/uk-UA/webtoolkit/download.html

2. Unzip it and move it to Applications folder on your Mac.

Install SmartGWT on Mac like this:

1. Download  SmartGWT from this site http://www.smartclient.com/product/download.jsp

2. Unzip it and move it to Applications folder on your Mac.

In Terminal set GWT_HOME and GST_HOME like this:

Open in Terminal with Vim .profile: vi ~/.profile

Add these lines:

export GWT_HOME=/Applications/gwt-2.1.1 (put here your version of gwt)

export GST_HOME=/Applications/smartgwt-2.4 (put here your version of smartgwt)

Restart your Mac and in Terminal check path to GWT_HOME and GST_HOME:

echo $GWT_HOME

echo $GST_HOME

That's all. 

How to Copy directory in Linux

Here is the command in Linux or Mac (in Terminal) that will make one directory to be copied into another:

cp -r one_directory other_directory.

Important add is the argument -r


Check this link about copy command in Linux.

VIM on Mac

When someone first trying VIM editor he will wondering how to finish VIM :) Here is how to do it.

HOW to save and close VIM on Mac:
Type only two characters: ZZ


Check this link for further instruction about commands of VIM.

Enter svn with username

svn --username login@domain.com list http://domain_of_repository

Install Maven (mvn) on Mac

First of all check version of Maven on your Mac with this command:
mvn --version


MacOS goes with Maven 3.0.2 preinstalled. If you will need mvn 2.2.1 go to this http://www.apache.org/dyn/closer.cgi/maven/binaries/apache-maven-2.2.1-bin.zip 
and download BINARY (!!!) NOT SRC (!!!) file of maven.


Create in ~/usr a new directory local.
Put into ~/usr/local/ this downloaded binary Maven.
Add to ~/.profile this line: 
export PATH=/usr/local/apache-maven-2.2.1/bin:$PATH


IMPORTANT!!! Reboot Mac. Then check again mvn --version and there should be maven 2.2.1.


Here is where to you should to set PATH for JAVA_HOME:


~/.profile


DON'T forget to changes properties of Maven version in IDE!
Here is example where to do it in NetBeans 7: