Hadoop is a framework written in Java for running applications on large clusters of commodity hardware and incorporates features similar to those of the Google File System (GFS) and of the MapReduce computing paradigm. Hadoop’s HDFS is a highly fault-tolerant distributed file system and, like Hadoop in general, designed to be deployed on low-cost hardware. It provides high throughput access to application data and is suitable for applications that have large data sets.
The main goal of this tutorial is to get a simple Hadoop installation up and running so that you can play around with the software and learn more about it.
While playing around with Lucene in my experiments to make it work with Google App Engine, I found an excellent example for indexing some text using Lucene in-memory; unfortunately, it dates back to May 2004 (!!!). I’ve updated the example to work with the newest version of Lucene, 3.0.1. It’s below for reference.
The Pastie link for the code snippet can be found here.
original post can be found on ikaisays
[Kostja Stern has been kind enough to translate this article in russian, which can be found here]
A virtual machine (VM) is a high level abstraction on top of the native operating system, that emulates a physical machine. Here, we are talking about process virtual machines and not system virtual machines. A virtual machine enables the same platform to run on multiple operating systems and hardware architectures. The Interpreters for Java and Python can be taken as examples, where the code is compiled into their VM specific bytecode. The same can be seen in the Microsoft .Net architecture, where code is compiled into intermediate language for the CLR (Common Language Runtime).
orginal post on markfaction
1. tar command examples
Create a new tar archive.
$ tar cvf archive_name.tar dirname/
Extract from an existing tar archive.
$ tar xvf archive_name.tar
View an existing tar archive.
$ tar tvf archive_name.tar
More tar examples: The Ultimate Tar Command Tutorial with 10 Practical Examples
2. grep command examples
Search for a given string in a file (case in-sensitive search).
$ grep -i "the" demo_file
Print the matched line, along with the 3 lines after it.
$ grep -A 3 -i "example" demo_text
Search for a given string in all files recursively
$ grep -r "ramesh" *
More grep examples: Get a Grip on the Grep! – 15 Practical Grep Command Examples
3. find command examples
Find files using file-name ( case in-sensitve find)
# find -iname "MyCProgram.c"
Execute commands on files found by the find command
$ find -iname "MyCProgram.c" -exec md5sum {} \;
Find all empty files in home directory
# find ~ -empty
More find examples: Mommy, I found it! — 15 Practical Linux Find Command Examples
4. ssh command examples
Login to remote host
ssh -l jsmith remotehost.example.com
Debug ssh client
ssh -v -l jsmith remotehost.example.com
Display ssh client version
$ ssh -V
OpenSSH_3.9p1, OpenSSL 0.9.7a Feb 19 2003
More ssh examples: 5 Basic Linux SSH Client Commands
5. sed command examples
When you copy a DOS file to Unix, you could find \r\n in the end of each line. This example converts the DOS file format to Unix file format using sed command.
$sed 's/.$//' filename
Print file content in reverse order
$ sed -n '1!G;h;$p' thegeekstuff.txt
Add line number for all non-empty-lines in a file
$ sed '/./=' thegeekstuff.txt | sed 'N; s/\n/ /'
More sed examples: Advanced Sed Substitution Examples
6. awk command examples
Remove duplicate lines using awk
$ awk '!($0 in array) { array[$0]; print }' temp
Print all lines from /etc/passwd that has the same uid and gid
$awk -F ':' '$3==$4' passwd.txt
Print only specific field from a file.
$ awk '{print $2,$5;}' employee.txt
More awk examples: 8 Powerful Awk Built-in Variables – FS, OFS, RS, ORS, NR, NF, FILENAME, FNR
7. vim command examples
Go to the 143rd line of file
$ vim +143 filename.txt
Go to the first match of the specified
$ vim +/search-term filename.txt
Open the file in read only mode.
$ vim -R /etc/passwd
More vim examples: How To Record and Play in Vim Editor
8. diff command examples
Ignore white space while comparing.
# diff -w name_list.txt name_list_new.txt
2c2,3
< John Doe --- > John M Doe
> Jason Bourne
More diff examples: Top 4 File Difference Tools on UNIX / Linux – Diff, Colordiff, Wdiff, Vimdiff
9. sort command examples
Sort a file in ascending order
$ sort names.txt
Sort a file in descending order
$ sort -r names.txt
Sort passwd file by 3rd field.
$ sort -t: -k 3n /etc/passwd | more
10. export command examples
To view oracle related environment variables.
$ export | grep ORACLE
declare -x ORACLE_BASE="/u01/app/oracle"
declare -x ORACLE_HOME="/u01/app/oracle/product/10.2.0"
declare -x ORACLE_SID="med"
declare -x ORACLE_TERM="xterm"
To export an environment variable:
$ export ORACLE_HOME=/u01/app/oracle/product/10.2.0
11. xargs command examples
Copy all images to external hard-drive
# ls *.jpg | xargs -n1 -i cp {} /external-hard-drive/directory
Search all jpg images in the system and archive it.
# find / -name *.jpg -type f -print | xargs tar -cvzf images.tar.gz
Download all the URLs mentioned in the url-list.txt file
# cat url-list.txt | xargs wget –c
12. ls command examples
Display filesize in human readable format (e.g. KB, MB etc.,)
$ ls -lh
-rw-r----- 1 ramesh team-dev 8.9M Jun 12 15:27 arch-linux.txt.gz
Order Files Based on Last Modified Time (In Reverse Order) Using ls -ltr
$ ls -ltr
Visual Classification of Files With Special Characters Using ls -F
$ ls -F
More ls examples: Unix LS Command: 15 Practical Examples
13. pwd command
pwd is Print working directory. What else can be said about the good old pwd who has been printing the current directory name for ages.
14. cd command examples
Use “cd -” to toggle between the last two directories
Use “shopt -s cdspell” to automatically correct mistyped directory names on cd
More cd examples: 6 Awesome Linux cd command Hacks
15. gzip command examples
To create a *.gz compressed file:
$ gzip test.txt
To uncompress a *.gz file:
$ gzip -d test.txt.gz
Display compression ratio of the compressed file using gzip -l
$ gzip -l *.gz
compressed uncompressed ratio uncompressed_name
23709 97975 75.8% asp-patch-rpms.txt
16. bzip2 command examples
To create a *.bz2 compressed file:
$ bzip2 test.txt
To uncompress a *.bz2 file:
bzip2 -d test.txt.bz2
More bzip2 examples: BZ is Eazy! bzip2, bzgrep, bzcmp, bzdiff, bzcat, bzless, bzmore examples
17. unzip command examples
To extract a *.zip compressed file:
$ unzip test.zip
View the contents of *.zip file (Without unzipping it):
$ unzip -l jasper.zip
Archive: jasper.zip
Length Date Time Name
-------- ---- ---- ----
40995 11-30-98 23:50 META-INF/MANIFEST.MF
32169 08-25-98 21:07 classes_
15964 08-25-98 21:07 classes_names
10542 08-25-98 21:07 classes_ncomp
18. shutdown command examples
Shutdown the system and turn the power off immediately.
# shutdown -h now
Shutdown the system after 10 minutes.
# shutdown -h +10
Reboot the system using shutdown command.
# shutdown -r now
Force the filesystem check during reboot.
# shutdown -Fr now
19. ftp command examples
Both ftp and secure ftp (sftp) has similar commands. To connect to a remote server and download multiple files, do the following.
$ ftp IP/hostname
ftp> mget *.html
To view the file names located on the remote server before downloading, mls ftp command as shown below.
ftp> mls *.html -
/ftptest/features.html
/ftptest/index.html
/ftptest/othertools.html
/ftptest/samplereport.html
/ftptest/usage.html
More ftp examples: FTP and SFTP Beginners Guide with 10 Examples
20. crontab command examples
View crontab entry for a specific user
# crontab -u john -l
Schedule a cron job every 10 minutes.
*/10 * * * * /home/ramesh/check-disk-space
More crontab examples: Linux Crontab: 15 Awesome Cron Job Examples
21. service command examples
Service command is used to run the system V init scripts. i.e Instead of calling the scripts located in the /etc/init.d/ directory with their full path, you can use the service command.
Check the status of a service:
# service ssh status
Check the status of all the services.
service --status-all
Restart a service.
# service ssh restart
22. ps command examples
ps command is used to display information about the processes that are running in the system.
While there are lot of arguments that could be passed to a ps command, following are some of the common ones.
To view current running processes.
$ ps -ef | more
To view current running processes in a tree structure. H option stands for process hierarchy.
$ ps -efH | more
23. free command examples
This command is used to display the free, used, swap memory available in the system.
Typical free command output. The output is displayed in bytes.
$ free
total used free shared buffers cached
Mem: 3566408 1580220 1986188 0 203988 902960
-/+ buffers/cache: 473272 3093136
Swap: 4000176 0 4000176
If you want to quickly check how many GB of RAM your system has use the -g option. -b option displays in bytes, -k in kilo bytes, -m in mega bytes.
$ free -g
total used free shared buffers cached
Mem: 3 1 1 0 0 0
-/+ buffers/cache: 0 2
Swap: 3 0 3
If you want to see a total memory ( including the swap), use the -t switch, which will display a total line as shown below.
ramesh@ramesh-laptop:~$ free -t
total used free shared buffers cached
Mem: 3566408 1592148 1974260 0 204260 912556
-/+ buffers/cache: 475332 3091076
Swap: 4000176 0 4000176
Total: 7566584 1592148 5974436
24. top command examples
top command displays the top processes in the system ( by default sorted by cpu usage ). To sort top output by any column, Press O (upper-case O) , which will display all the possible columns that you can sort by as shown below.
Current Sort Field: P for window 1:Def
Select sort field via field letter, type any other key to return
a: PID = Process Id v: nDRT = Dirty Pages count
d: UID = User Id y: WCHAN = Sleeping in Function
e: USER = User Name z: Flags = Task Flags
........
To displays only the processes that belong to a particular user use -u option. The following will show only the top processes that belongs to oracle user.
$ top -u oracle
More top examples: Can You Top This? 15 Practical Linux Top Command Examples
25. df command examples
Displays the file system disk space usage. By default df -k displays output in bytes.
$ df -k
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda1 29530400 3233104 24797232 12% /
/dev/sda2 120367992 50171596 64082060 44% /home
df -h displays output in human readable form. i.e size will be displayed in GB’s.
ramesh@ramesh-laptop:~$ df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 29G 3.1G 24G 12% /
/dev/sda2 115G 48G 62G 44% /home
Use -T option to display what type of file system.
ramesh@ramesh-laptop:~$ df -T
Filesystem Type 1K-blocks Used Available Use% Mounted on
/dev/sda1 ext4 29530400 3233120 24797216 12% /
/dev/sda2 ext4 120367992 50171596 64082060 44% /home
26. kill command examples
Use kill command to terminate a process. First get the process id using ps -ef command, then use kill -9 to kill the running Linux process as shown below. You can also use killall, pkill, xkill to terminate a unix process.
$ ps -ef | grep vim
ramesh 7243 7222 9 22:43 pts/2 00:00:00 vim
$ kill -9 7243
More kill examples: 4 Ways to Kill a Process – kill, killall, pkill, xkill
27. rm command examples
Get confirmation before removing the file.
$ rm -i filename.txt
It is very useful while giving shell metacharacters in the file name argument.
Print the filename and get confirmation before removing the file.
$ rm -i file*
Following example recursively removes all files and directories under the example directory. This also removes the example directory itself.
$ rm -r example
28. cp command examples
Copy file1 to file2 preserving the mode, ownership and timestamp.
$ cp -p file1 file2
Copy file1 to file2. if file2 exists prompt for confirmation before overwritting it.
$ cp -i file1 file2
29. mv command examples
Rename file1 to file2. if file2 exists prompt for confirmation before overwritting it.
$ mv -i file1 file2
Note: mv -f is just the opposite, which will overwrite file2 without prompting.
mv -v will print what is happening during file rename, which is useful while specifying shell metacharacters in the file name argument.
$ mv -v file1 file2
30. cat command examples
You can view multiple files at the same time. Following example prints the content of file1 followed by file2 to stdout.
$ cat file1 file2
While displaying the file, following cat -n command will prepend the line number to each line of the output.
$ cat -n /etc/logrotate.conf
1 /var/log/btmp {
2 missingok
3 monthly
4 create 0660 root utmp
5 rotate 1
6 }
31. mount command examples
To mount a file system, you should first create a directory and mount it as shown below.
# mkdir /u01
# mount /dev/sdb1 /u01
You can also add this to the fstab for automatic mounting. i.e Anytime system is restarted, the filesystem will be mounted.
/dev/sdb1 /u01 ext2 defaults 0 2
32. chmod command examples
chmod command is used to change the permissions for a file or directory.
Give full access to user and group (i.e read, write and execute ) on a specific file.
$ chmod ug+rwx file.txt
Revoke all access for the group (i.e read, write and execute ) on a specific file.
$ chmod g-rwx file.txt
Apply the file permissions recursively to all the files in the sub-directories.
$ chmod -R ug+rwx file.txt
More chmod examples: 7 Chmod Command Examples for Beginners
33. chown command examples
chown command is used to change the owner and group of a file. \
To change owner to oracle and group to db on a file. i.e Change both owner and group at the same time.
$ chown oracle:dba dbora.sh
Use -R to change the ownership recursively.
$ chown -R oracle:dba /home/oracle
34. passwd command examples
Change your password from command line using passwd. This will prompt for the old password followed by the new password.
$ passwd
Super user can use passwd command to reset others password. This will not prompt for current password of the user.
# passwd USERNAME
Remove password for a specific user. Root user can disable password for a specific user. Once the password is disabled, the user can login without entering the password.
# passwd -d USERNAME
35. mkdir command examples
Following example creates a directory called temp under your home directory.
$ mkdir ~/temp
Create nested directories using one mkdir command. If any of these directories exist already, it will not display any error. If any of these directories doesn’t exist, it will create them.
$ mkdir -p dir1/dir2/dir3/dir4/
36. ifconfig command examples
Use ifconfig command to view or configure a network interface on the Linux system.
View all the interfaces along with status.
$ ifconfig -a
Start or stop a specific interface using up and down command as shown below.
$ ifconfig eth0 up
$ ifconfig eth0 down
More ifconfig examples: Ifconfig: 7 Examples To Configure Network Interface
37. uname command examples
Uname command displays important information about the system such as — Kernel name, Host name, Kernel release number,
Processor type, etc.,
Sample uname output from a Ubuntu laptop is shown below.
$ uname -a
Linux john-laptop 2.6.32-24-generic #41-Ubuntu SMP Thu Aug 19 01:12:52 UTC 2010 i686 GNU/Linux
38. whereis command examples
When you want to find out where a specific Unix command exists (for example, where does ls command exists?), you can execute the following command.
$ whereis ls
ls: /bin/ls /usr/share/man/man1/ls.1.gz /usr/share/man/man1p/ls.1p.gz
When you want to search an executable from a path other than the whereis default path, you can use -B option and give path as argument to it. This searches for the executable lsmk in the /tmp directory, and displays it, if it is available.
$ whereis -u -B /tmp -f lsmk
lsmk: /tmp/lsmk
39. whatis command examples
Whatis command displays a single line description about a command.
$ whatis ls
ls (1) - list directory contents
$ whatis ifconfig
ifconfig (8) - configure a network interface
40. locate command examples
Using locate command you can quickly search for the location of a specific file (or group of files). Locate command uses the database created by updatedb.
The example below shows all files in the system that contains the word crontab in it.
$ locate crontab
/etc/anacrontab
/etc/crontab
/usr/bin/crontab
/usr/share/doc/cron/examples/crontab2english.pl.gz
/usr/share/man/man1/crontab.1.gz
/usr/share/man/man5/anacrontab.5.gz
/usr/share/man/man5/crontab.5.gz
/usr/share/vim/vim72/syntax/crontab.vim
41. man command examples
Display the man page of a specific command.
$ man crontab
When a man page for a command is located under more than one section, you can view the man page for that command from a specific section as shown below.
$ man SECTION-NUMBER commandname
Following 8 sections are available in the man page.
General commands
System calls
C library functions
Special files (usually devices, those found in /dev) and drivers
File formats and conventions
Games and screensavers
Miscellaneous
System administration commands and daemons
For example, when you do whatis crontab, you’ll notice that crontab has two man pages (section 1 and section 5). To view section 5 of crontab man page, do the following.
$ whatis crontab
crontab (1) - maintain crontab files for individual users (V3)
crontab (5) - tables for driving cron
$ man 5 crontab
42. tail command examples
Print the last 10 lines of a file by default.
$ tail filename.txt
Print N number of lines from the file named filename.txt
$ tail -n N filename.txt
View the content of the file in real time using tail -f. This is useful to view the log files, that keeps growing. The command can be terminated using CTRL-C.
$ tail -f log-file
More tail examples: 3 Methods To View tail -f output of Multiple Log Files in One Terminal
43. less command examples
less is very efficient while viewing huge log files, as it doesn’t need to load the full file while opening.
$ less huge-log-file.log
One you open a file using less command, following two keys are very helpful.
CTRL+F – forward one window
CTRL+B – backward one window
More less examples: Unix Less Command: 10 Tips for Effective Navigation
44. su command examples
Switch to a different user account using su command. Super user can switch to any other user without entering their password.
$ su - USERNAME
Execute a single command from a different account name. In the following example, john can execute the ls command as raj username. Once the command is executed, it will come back to john’s account.
[john@dev-server]$ su - raj -c 'ls'
[john@dev-server]$
Login to a specified user account, and execute the specified shell instead of the default shell.
$ su -s 'SHELLNAME' USERNAME
45. mysql command examples
mysql is probably the most widely used open source database on Linux. Even if you don’t run a mysql database on your server, you might end-up using the mysql command ( client ) to connect to a mysql database running on the remote server.
To connect to a remote mysql database. This will prompt for a password.
$ mysql -u root -p -h 192.168.1.2
To connect to a local mysql database.
$ mysql -u root -p
If you want to specify the mysql root password in the command line itself, enter it immediately after -p (without any space).
46. yum command examples
To install apache using yum.
$ yum install httpd
To upgrade apache using yum.
$ yum update httpd
To uninstall/remove apache using yum.
$ yum remove httpd
47. rpm command examples
To install apache using rpm.
# rpm -ivh httpd-2.2.3-22.0.1.el5.i386.rpm
To upgrade apache using rpm.
# rpm -uvh httpd-2.2.3-22.0.1.el5.i386.rpm
To uninstall/remove apache using rpm.
# rpm -ev httpd
More rpm examples: RPM Command: 15 Examples to Install, Uninstall, Upgrade, Query RPM Packages
48. ping command examples
Ping a remote host by sending only 5 packets.
$ ping -c 5 gmail.com
More ping examples: Ping Tutorial: 15 Effective Ping Command Examples
49. date command examples
Set the system date:
# date -s "01/31/2010 23:59:53"
Once you’ve changed the system date, you should syncronize the hardware clock with the system date as shown below.
# hwclock –systohc
# hwclock --systohc –utc
50. wget command examples
The quick and effective method to download software, music, video from internet is using wget command.
$ wget http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-3.2.1.tar.gz
Download and store it with a different name.
$ wget -O taglist.zip http://www.vim.org/scripts/download_script.php?src_id=7701
More wget examples: The Ultimate Wget Download Guide With 15 Awesome Examples
Did I miss any frequently used Linux commands? Leave a comment and let me know.
eclipse help
With eclipse open go to the Help -> Install new software section
*remember to start eclipse with administrator privelages if you are using Windows 7.
Add a new site titled UIMA with the address http://www.apache.org/dist/uima/eclipse-update-site/
Install both the Apache UIMA Eclipse tooling and runtime support package and the Apache UIMA-AS Eclipse tooling package.
Restart Eclipse
Using UIMA-AS to run UIMA annotators in parallel
Overview
UIMA stands for Unstructured Information Management Architecture. It’s an Apache technology that provides a framework and standard for building text analytics applications. I’ve mentioned it before.
In this post, I want to talk about an area of UIMA which isn’t covered well in the documentation.
I couldn’t find practical getting-started instructions for running UIMA-AS annotators in parallel. In this post I want to discuss why you might want to do it, and share some simple sample code to show how.
Background – the UIMA pipeline
UIMA provides a framework for managing a text analytics application. You break up the analytics functionality into discrete pieces called annotators. UIMA takes care of moving a text document through an analytics engine: a pipeline containing a series of annotators.
A document goes in one end of the pipeline, passes through a number of annotators, each of which adds some metadata to the document. What comes out the other side of the pipeline is an annotated copy of the document.
By default, you get UIMA to run these annotators one at a time – one after another.
Background – annotators in parallel
What if your annotators are quite slow – perhaps they take several seconds to run?
If there is no dependency between any or all of your annotators, then maybe running them one at a time isn’t the most efficient approach.
You can run all of them at the same time, in parallel. UIMA will merge the output from all of the annotators into a single annotated document.
My sample code
I’ve written two sample UIMA apps. Each demonstrates one of these approaches, to compare and contrast.
They are divided into three eclipse projects. You can import them into an eclipse IDE.
The UIMA eclipse plugins are very helpful if you want to make changes to the XML configuration files, but they’re not essential. If you want them, there are instructions on how to install them at uima.apache.org.
I’ve added comments to the sample code to explain how the apps work, but I’ll give an overview here.
For these samples, I have five simple annotators. They sleep for six seconds, then add an empty annotation to the document CAS.
public void process(JCas jCas) throws AnalysisEngineProcessException {
// sleep for six seconds...
try {
Thread.sleep(6000);
}
catch (InterruptedException e) {
e.printStackTrace();
}
// add an empty annotation to the CAS
jCas.addFsToIndexes(new AnnotationB(jCas));
}
They do enough to prove that all five of them are being run, and that they all really contribute to the final annotated document. They take long enough to demonstrate the differences between these two approaches to running the pipeline.
Sample code : running one annotator at a time
This can be done using UIMA. The first app uima-project demonstrates this.
An XML descriptor file (uima-project/conf/analysisEngine.xml) specifies which annotators should be included in the pipeline, and which order they should be run in.
UIMA demonstration1.0annotatorAannotatorBannotatorCannotatorDannotatorE
The descriptor file (uima-project/conf/analysisEngine.xml) imports a descriptor for each individual annotator.
Each of those imported descriptors identifies the Java class that implements the annotator, and specifies the metadata annotations that it can add to the output document.
For example,
uima-project/conf/annotatorC/analysisEngine.xml:
com.dalelane.uima.annotators.DemoCannotatorCcom.dalelane.uima.annotators.gen.AnnotationCuima.tcas.Annotation
The overall pipeline is started from
uima-project/src/com/dalelane/uima/serial/Pipeline.java. This reads in the descriptor file for the pipeline, and uses it to create an instance of a UIMA analysis engine.
File descriptorFile = new File("./conf/analysisEngine.xml");
XMLInputSource descriptorSource = new XMLInputSource(descriptorFile);
ResourceSpecifier specifier = UIMAFramework.getXMLParser().parseResourceSpecifier(descriptorSource);
analysisEngine = UIMAFramework.produceAnalysisEngine(specifier);
To summarise:
The provided eclipse launch config starts a Java application
uima-project/src/com/dalelane/uima/serial/Application.java
The Java application creates
uima-project/src/com/dalelane/uima/serial/Pipeline.java which creates a UIMA AnalysisEngine
The analysis engine reads in the XML descriptor file uima-project/conf/analysisEngine.xml
The analysis engine descriptor identifies the descriptors for each annotator
(e.g. uima-project/conf/annotatorC/analysisEngine.xml)
The descriptor for the annotator identifies the Java class which implements it
(e.g. uima-project/src/com/dalelane/uima/annotators/DemoC.java )
The output from running the launch config shows that it takes about 30 seconds (5 annotators, each of which takes about 6 seconds) to process the document text.
Sample UIMA application - serial
==================================
Accessing analysis engine descriptor file
Creating analysis engine
Processing document...
Time spent in pipeline: 30121
Confirming what was added...
Found: org.apache.uima.jcas.tcas.Annotation
Found: com.dalelane.uima.annotators.gen.AnnotationD
Found: com.dalelane.uima.annotators.gen.AnnotationC
Found: com.dalelane.uima.annotators.gen.AnnotationB
Found: com.dalelane.uima.annotators.gen.AnnotationA
Sample code : running all annotators at once
This can be done using UIMA-AS – a variant of UIMA that provides support for asynchronous scale out. The second app uima-as-project demonstrates this.
To describe the approach at a high level, the idea is that you want to create five separate copies of the document to be analysed. Each of these copies can be run through a separate annotator at the same time. Once they’ve all finished, the output from all of the annotators can be collected together and merged to form the single output document.
Each of the annotators are run as a separate service. A by-product of this is that each can be run on a remote machine, and UIMA-AS manages moving the documents to/from the remote services using JMS messaging.
In my sample, I’m running them all on the same server, and using “localhost” to define the interactions. A JMS broker is still required for this. Instructions for starting the message broker is contained in uima-as-project/README
Because the annotators are run as “remote” services, this introduces an extra step – the services need to be deployed before the pipeline can be started.
uima-as-project/src/com/dalelane/uima/parallel/Pipeline.java deploys each of the services by specifying the deployment descriptors.
// creating UIMA analysis engine
UimaAsynchronousEngine uimaAsEngine = new BaseUIMAAsynchronousEngine_impl();
// preparing map for use in deploying services
Map deployCtx = new HashMap();
deployCtx.put(UimaAsynchronousEngine.DD2SpringXsltFilePath, System.getenv("UIMA_HOME") + "/bin/dd2spring.xsl");
deployCtx.put(UimaAsynchronousEngine.SaxonClasspath, "file:" + System.getenv("UIMA_HOME") + "/saxon/saxon8.jar");
// preparing map for use in deploying services
uimaAsEngine.deploy("./conf/annotatorA/deploy.xml", deployCtx);
uimaAsEngine.deploy("./conf/annotatorB/deploy.xml", deployCtx);
uimaAsEngine.deploy("./conf/annotatorC/deploy.xml", deployCtx);
uimaAsEngine.deploy("./conf/annotatorD/deploy.xml", deployCtx);
uimaAsEngine.deploy("./conf/annotatorE/deploy.xml", deployCtx);
The deployment descriptors for each annotator specify the name of the JMS endpoint that UIMA can use to send documents to the annotator for analysis, and the location of the analysis engine descriptor file that defines the annotator.
For example uima-as-project/conf/annotatorB/deploy.xml
The individual annotator descriptors are the same as in the first project uima-project.
For example,
uima-as-project/conf/annotatorB/analysisEngine.xml
As before, it identifies the Java class which implements the annotator, and the types of annotations that it can create.
Once the UIMA services are deployed, the analysis engine descriptor for the overall pipeline can be deployed.
This is also done in
uima-as-project/src/com/dalelane/uima/parallel/Pipeline.java
uimaAsEngine.deploy("./conf/deploy.xml", deployCtx);
The deployment descriptor for the overall pipeline (uima-as-project/conf/deploy.xml), identifies how the pipeline can communicate with each of the “remote” services that make up it’s annotators.
UIMA-AS provides a sample (AdvancedFixedFlowController) that takes care of making the copies (a CAS Multiplier) of the document being analysed, and defines the sequence for the annotators to be run in parallel.
The deployment descriptor for my pipeline uses this sample.
FlowannotatorA,annotatorB,annotatorC,annotatorD,annotatorE
It also identifies the descriptor file for running the analysis engine
The analysis engine descriptor file (uima-as-project/conf/analysisEngine.xml), similar to before, identifies the annotators that make up the aggregate pipeline.
These describe the way that the analysis engine can send documents to the remote services for analysis, using JMS. For example, uima-as-project/conf/annotatorB/remote.xml contains:
org.apache.uima.aae.jms_adapter.JmsAnalysisEngineServiceAdapter
To summarise:
The provided eclipse launch config starts a Java application uima-as-project/src/com/dalelane/uima/parallel/Application.java
The Java application creates an instance of uima-as-project/src/com/dalelane/uima/parallel/Pipeline.java
Pipeline.java creates an UimaAsynchronousEngine which deploys each of the annotator services, such as uima-as-project/conf/annotatorD/deploy.xml
Each annotator’s deployment descriptor identifies the actual implementation of the annotator, giving the analysis engine XML uima-as-project/conf/annotatorD/analysisEngine.xml which in turn specifies the Java implementation class
Pipeline.java then deploys the overall analysis engine pipeline as specified in the deployment descriptor uima-as-project/conf/deploy.xml
This deployment descriptor identifies the way that the analysis engine should communicate with the remote services (by importing JMS specs such as uima-as-project/conf/annotatorC/remote.xml) and the order that they should be invoked in (using AdvancedFixedFlowController)
The output from running the launch config shows that it takes about 6 seconds (5 annotators run in parallel, each of which takes about 6 seconds) to process the document text.
Full sample output is at
uima-as-project/example-output/console.log
A summary is:
Sample UIMA application - parallel
==================================
Deploying UIMA services
Service:annotatorA Initialized. Ready To Process Messages From Queue:AnnotatorARemoteQ
Service:annotatorB Initialized. Ready To Process Messages From Queue:AnnotatorBRemoteQ
Service:annotatorC Initialized. Ready To Process Messages From Queue:AnnotatorCRemoteQ
Service:annotatorD Initialized. Ready To Process Messages From Queue:AnnotatorDRemoteQ
Service:annotatorE Initialized. Ready To Process Messages From Queue:AnnotatorERemoteQ
Deploying analysis engine
Service:UIMA demonstration Initialized. Ready To Process Messages From Queue:DemoAnnotatorQueue
Initialising UIMA client
Processing document...
Time spent in pipeline: 6117
Confirming what was added...
Found: org.apache.uima.cas.impl.AnnotationImpl
Found: org.apache.uima.cas.impl.AnnotationImpl
Found: org.apache.uima.cas.impl.AnnotationImpl
Found: org.apache.uima.cas.impl.AnnotationImpl
Found: org.apache.uima.cas.impl.AnnotationImpl
Found: org.apache.uima.cas.impl.AnnotationImpl
Summary
This isn’t definitive model code for using UIMA-AS. It’s intended more as a helpful first step into getting started with UIMA-AS – which there seems to be a shortage of documentation for. But there is a *lot* more to UIMA-AS, with a lot of settings and features to tweak.
Even with this simple example, you can see that output which takes 30 seconds to get using UIMA can be completed in 6 seconds if run in parallel, and how this can be done with UIMA-AS and a few extra config files.
Tags: java, jms, uima, uima-as
original posts link
http://dalelane.co.uk/blog/?p=2247
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more on click here
Windows 8 now uses Internet Explorer's
SmartScreen system-wide, checking downloaded files to ensure they're
safe. In general this is a good thing, but if you have any problems then
it can be tweaked.
Launch Control Panel, open the Action Centre
applet, and click Change Windows SmartScreen Settings in the left-hand
pane. Here you can keep the warning, but avoid the requirement for
administrator approval, or turn SmartScreen off altogether. Make your
choice and click OK to finish.
28. Windows 8 File History
Windows
8 includes an excellent File History feature, which can regularly and
automatically back up your libraries, desktop, contacts and favourites
to a second drive (even a USB flash drive - just connect it, and choose
'Configure this drive for backup using File History' from the menu).
To
set this up, go to Control Panel > System and Security > File
History. Click Exclude Folders to help define what you're saving,
Advanced Settings to choose the backup frequency, Change Drive to choose
the backup destination, and Turn On to enable the feature with your
settings.
And once it's been running for a while, you can check on
the history for any file in Explorer by selecting it, choosing the Home
tab and clicking History.
29. VHD - enhanced
Windows
7 added support for creating and attaching virtual hard drives in
Microsoft's VHD format. Now Windows 8 extends this with the new VHDX
format, which improves performance, extends the maximum file size from 2
to 16TB, and makes the format "more resilient to power failure events"
(so they shouldn't get corrupted as easily). Launch the Computer
Management Control Panel applet, choose Disk Management, and click
Actions > Create VHD to give the format a try.
30. Storage Spaces
If
you have multiple hard drives packed with data then you'll know that
managing them can be a hassle. But that's all about to change with a new
Windows 8 feature, Storage Spaces.
The idea is that you can take
all your hard drives, whether connected via USB, SATA or SAS (Serial
Attached SCSI), and add them to a storage pool. And you can then create
one or more spaces within this pool, formatting and accessing them as a
single drive, so you've only one drive letter to worry about.
What's
more, the technology can also maximise your performance by spreading
files across multiple drives (the system can then access each chunk
simultaneously). There's an option to mirror your files, too, so even if
one disk fails your data remains safe. And if your Storage Space begins
to fill up then just plug in another drive, add it to the pool and you
can carry on as before.
Yes, we know, this is just a
consumer-friendly take on RAID. But there's nothing wrong with that, and
it looks promising. If you'd like to read up on the technical details
then the official Windows 8 blog
has more, and you can then create and manage your drive pool from the
new Control Panel\System and Security 'Storage Spaces' applet.
31. Virtual Machines
Install
Windows 8 and you also get Microsoft's Hyper-V, enabling you to create
and run virtual machines (as long as you're not running in a virtual
machine already). Launch OptionalFeatures.exe (press Windows Key and R
and type it in to run), check Hyper-V and click OK to enable the
feature. Then switch back to the Start screen, scroll to the right, find
and click on the Hyper-V Manager tile to begin exploring its
capabilities.
32. Smart Searching
When you're in the mood
to track down new Windows 8 features relating to a particular topic, you
might be tempted to start by manually browsing Control Panel for
interesting applets - but there is a simpler way.
If you'd like to
know what's new in the area of storage, say, just press Win+W to launch
the Settings Search dialog, type "drive", and the system will return a
host of related options. That is, not just those with "drive" in the
name, but anything storage-related: BitLocker, Device Manager, backup
tools, disk cleanup, and interesting new features such as Storage
Spaces.
This Search feature isn't new, of course, but it's easy to
forget how useful this can be, especially when you're trying to learn
about a new operating system. So don't just carry out specific searches,
use the Apps search to look for general keywords such as "privacy" or
"performance", and you just might discover something new.
If you like your PC to boot just
as fast as possible then the new Windows 8 lock screen may not appeal.
Don't worry, though, if you'd like to ditch this then it only takes a
moment.
Launch GPEdit.msc (the Local Group Policy Editor) and
browse to Computer Configuration > Administrative Templates >
Control Panel > Personalisation.
Double-click 'Do not display the lock screen', select Enabled and click OK.
Restart and the lock screen will have gone.
If
you can't easily find GPEdit.msc by searching in the Start screen,
search for 'mmc', and then press Enter. On the File menu, click
'Add/Remove Snap-in', then in the 'Add or Remove Snap-ins' dialog box,
click 'Group Policy Object Editor', and then click 'Add'.
In the
'Select Group Policy Object' dialog box, click 'Browse'. Click 'This
Computer' to edit the Local Group Policy object, or click 'Users' to
edit Administrator, Non-Administrator, or per-user Local Group Policy
objects, then click 'Finish'.
20. Install anything
Most
mobile platforms recommend you only install apps from approved sources
to protect your security, and Windows 8 is the same: it'll only allow
you to install trusted (that is, digitally signed) apps from the Windows
store.
If this proves a problem, though, and you're willing to
take the security risk (because this isn't something to try unless
you're entirely sure it's safe), then the system can be configured to
run trusted apps from any source.
Launch GPEdit.msc (see above
for instructions on how to find it), browse to Computer Configuration
> Administrative Templates > Windows Components > App Package
Deployment, double-click 'Allow all trusted apps to install' and select
Enabled > OK.
21. Log in automatically
Of
course even if you remove the lock screen, you'll still be forced to
manually log in every time your system starts. This can also be resolved
at speed, though, using much the same technique as in previous versions
of Windows.
Hold down the Windows key, press R, type 'netplwiz' and press Enter to launch the User Accounts dialog.
Clear the "Users must enter a user name and password to use this computer" box and click OK.
Enter
the user name and password of the account that you'd like to be logged
in automatically, click OK, restart your system and this time it should
boot directly to the Start screen.
22. Replacing the Start menu
If Windows 8's search and navigation tools still leave you pining for the regular Start menu, installing ViStart will replace it with something very similar.
Download
the program and install it, carefully; it's free, but the Setup program
will install the trial of a commercial Registry cleaner unless you
explicitly tell it otherwise.
But once that's out the way, your
old Start button will return in its regular place, and clicking it (or
pressing the Windows key) will bring back the usual Start menu complete
with search box and all the usual menus.
The program has a few flaws - on launch it gave us an e-mail icon for Outlook Express, for instance - but otherwise works well.
There's also Start8 from Windows customisation veterans Stardock. It provides similar functionality to ViStart but with a more up-to-date look.
23. Windows key shortcuts
Win : switch between the Start screen and the last-running Windows 8 app
Win + C : displays the Charms: the Settings, Devices, Share and Search options
Win + D : launches the desktop
Win + E : launches Explorer
Win + F : opens the File Search pane
Win + H : opens the Share pane
Win + I : opens Settings
Win + K : opens the Devices pane
Win + L : locks your PC
Win + M : minimises the current Explorer or Internet Explorer window (works in the full-screen IE, too)
Win + O : toggles device orientation lock on and off
Win + P : switch your display to a second display or projector
Win + Q : open the App Search pane
Win + R : opens the Run box
Win + U : open the Ease of Access Centre
Win + V : cycle through toasts (notifications)
Win + W : search your system settings (type POWER for links to all power-related options, say)
Win + X : displays a text menu of useful Windows tools and applets
Win + Z : displays the right-click context menu when in a full-screen app
Win + + : launch Magnifier and zoom in
Win + - : zoom out
Win + , : Aero peek at the desktop
Win + Enter : launch Narrator
Win + PgUp : move the current screen to the left-hand monitor
Win + PgDn : move the current screen to the right-hand monitor
Win + PrtSc : capture the current screen and save it to your Pictures folder
If
you're a fan of keyboard shortcuts and don't like the idea of scrolling
through app tiles to find the program you need, don't worry, Windows 8
still supports a useful old shortcut. Which is perfect if, say, you're
looking to be able to shut down your PC with a click.
Launch the desktop app, right-click an empty part of the desktop and click New > Shortcut.
Browse to the application you'd like to launch here. Of for the sake of this example, enter shutdown.exe -s -t 00
to shut down your PC, or shutdown.exe -h -t 00
to hibernate it, and click Next. Type a shortcut name - 'Hibernate', say - and click Finish.
Right-click
the shortcut, select Pin to Start and it should appear on the far right
of the Start screen - just drag the tile wherever you like.
25. Intelligent screengrabs
If
a Windows 8 application is showing something interesting and you'd like
to record it for posterity, then hold down the Windows key, press
PrtSc, and the image won't just go to the clipboard: it'll also be
automatically saved to your My Pictures folder with the name
Screenshot.png (and then Screenshot(1).png, Screenshot(2).png and so
on).
You might hope that pressing Win+Alt+PrtSc would similarly
save an image of the active window, but no, sadly not. Maybe next time.
26. Photo Viewer
Double-click
an image file within Explorer and it won't open in a Photo Viewer
window any more, at least not by default. Instead you'll be switched to
the full-screen Windows 8 Photos app - bad news if you thought you'd
escaped such hassles by using the desktop.
If you'd like to fix this, go to Control Panel > Programs > Default Programs and select Set your default programs.
Scroll down and click Windows Photo Viewer in the Programs list.
Finally,
click 'Set this program as default' if you'd like the Viewer to open
all the file types it can handle, or select the 'Choose default' options
if you prefer to specify which file types it should open. Click OK when
you're done.
Windows 8 apps aim to be simpler than old-style
Windows applets, which means it's goodbye to menus, complex toolbars,
and many interface standards. There will usually be a few options
available on the App bar, though, so if you're unsure what to do then
either right-click an empty part of the screen, press Windows+Z or flick
your finger up from the bottom of the screen to take a closer look.
9. What's running?
If
you launch a Windows 8 app, play with it for a while, then press the
Windows key you'll switch back to the Start screen. Your app will
remaining running, but as there's no taskbar then you might be wondering
how you'd ever find that out.
You could just press Alt+Tab, which shows you what's running just as it always has.
Holding
down the Windows key and pressing Tab displays a pane on the left-hand
side of the screen with your running apps. (To see this with the mouse,
move your cursor to the top left corner of the screen, wait until the
thumbnail of one app appears, then drag down.)
And of course you
can always press Ctrl+Shift+Esc to see all your running apps in the Task
Manager, if you don't mind (or actually need) the extra technical
detail.
Windows
8 apps don't have close buttons, but this isn't the issue you might
think. Apps are suspended when you switch to something else so they're
only a very minimal drain on your system, and if you need the system
resources then they'll automatically be shut down. (Their context will
be saved, of course, so on relaunching they'll carry on where you left
off.)
If you want to close down an app anyway, though, move the
mouse cursor up to the top of the screen. When it turns from the regular
mouse pointer to the icon of a hand, hold down the left mouse button
and drag it down the screen. Your app should shrink to a thumbnail which
you can drag off the screen to close it.
If that's too much hassle, then simply pressing Alt+F4 still works.
And
when all else fails then press Ctrl+Shift+Esc to launch Task Manager,
right-click something in the Apps list and select End Task. Beware,
though, close something you shouldn't and it's easy to crash or lock up
your PC.
11. Mastering Internet Explorer in Windows 8
Click
the Internet Explorer tile from the Start menu and you'll launch a
full-screen version without toolbars, menus or sidebars, which like so
much of Windows 8 may leave you initially feeling lost.
Right-click
an empty part of the page or flick your finger down from the top of the
screen, though, and you'll find options to create and switch between
tabs, as well as a Refresh button, a 'Find' tool and the ability to pin
an Internet shortcut to the Start page. Click the spanner icon and
select 'View on the desktop' to open the full desktop version of
Internet Explorer.
12. Run two apps side by side
Windows
8 apps are what Microsoft calls "immersive" applications, which
basically means they run full-screen - but there is a way to view two at
once. Swipe from the left and the last app you were using will turn
into a thumbnail; drop this and one app displays in a sidebar pane while
your current app takes the rest of the screen. And you can then swap
these by swiping again.
13. Spell check
Windows
8 apps all have spellcheck where relevant, which looks and works much
as it does in Microsoft Office. Make a mistake and a wavy red line will
appear below the offending word; tap or right-click this to see
suggested alternative words, or add the word to your own dictionary if
you prefer.
14. Run as Administrator
Some programs need
you to run them with Administrator rights before they'll work properly.
The old context menu isn't available for a pinned Start screen app, but
right-click one, and if it's appropriate for this app then you'll see a
Run As Administrator option.
15. Make a large app tile smaller
You'll
notice that some Windows 8 apps have small live tiles, while others
have larger tiles that take up the space of two tiles. Right-clicking on
a Windows 8 app's Start screen tile will display a few relevant
options. If this is one of the larger tiles, choosing 'Smaller' will cut
it down to half the size, freeing up some valuable Start screen real
estate.
16. Uninstall easily
If you want to hide an unused
app for now, select 'Unpin from Start'. The tile will disappear, but if
you change your mind then you can always add it again later. (Search
for the app, right-click it, select 'Pin to Start'.)
Or, if you're sure you'll never want to use an app again, choose 'Uninstall' to remove it entirely.
17. Apps and privacy
It
is worth keeping in mind that by default Windows 8 apps can use your
name, location and account picture. If you're not happy with that, it's
easily changed. Press Win+I, click More PC Settings, select Privacy and
click the relevant buttons to disable any details you'd rather not
share.
18. Administrative tools
Experienced
Windows users who spend much of their time in one advanced applet or
another are often a little annoyed to see their favourite tools buried
by Windows 8. Microsoft has paid at least some attention, though, and
there is a way to bring some of them back.
Open the Charm bar by
flicking your finger from the right-hand side of the screen and select
'Settings' then 'Tiles'. Change 'Show administrative tools' to 'Yes' and
click back on an empty part of the Start screen. And it's as simple as
that. Scroll to the right and you'll find a host of new tiles for
various key applets - Performance Monitor, Event Viewer, Task Scheduler,
Resource Monitor and more - ready to be accessed at a click.
Windows 8 is finally here, and if you're used to previous versions of
Windows then you're going to notice that quite a bit has changed. In
fact, Windows has seen the biggest changes since the jump from Windows
3.1 to Windows 95.
Out goes the Start menu, in comes the new
touch-oriented Start screen, new apps, new interface conventions - even
experienced PC users may be left feeling a little lost.
Don't
despair, though, help is at hand. We've been investigating every part of
Windows 8, uncovering many of its most important tips and tricks, so
read our guide and you'll soon be equipped to get the most out of
Microsoft's latest release.
1. Lock screen
Windows 8 opens on its lock screen, which looks pretty but unfortunately displays no clues about what to do next.
It's
all very straightforward, though. Just tap the space bar, spin the
mouse wheel or swipe upwards on a touch screen to reveal a regular login
screen with the user name you created during installation. Enter your
password to begin.
2. Basic navigation
Windows 8 launches
with its new interface, all colourful tiles and touch-friendly apps. And
if you're using a tablet then it'll all be very straightforward: just
swipe left or right to scroll the screen, and tap any tile of interest.
On a regular desktop, though, you might alternatively spin the mouse wheel to scroll backwards and forwards.
And
you can also use the keyboard. Press the Home or End keys to jump from
one end of your Start screen to the other, for instance, then use the
cursor keys to select a particular tile, tapping Enter to select it.
Press the Windows key to return to the Start screen; right-click (or
swipe down on) apps you don't need and select Unpin to remove them; and
drag and drop the other tiles around to organise them as you like.
3. App groups
The Start screen apps are initially displayed
in a fairly random order, but if you'd prefer a more organised life then
it's easy to sort them into custom groups.
You might drag People,
Mail, Messaging and Calendar over to the left-hand side, for instance,
to form a separate 'People' group. Click the 'minus' icon in the bottom
right corner of the screen to zoom out and you'll now find you can drag
and drop the new group (or any of the others) around as a block.
Right-click
within the block (while still zoomed out) and you'll also be able to
give the group a name, which - if you go on to add another 20 or 30 apps
to your Start screen - will make it much easier to find the tools you
need.
4. Quick access menu
Right-click
in the bottom left corner (or hold down the Windows key and press X)
for a text-based menu that provides easy access to lots of useful
applets and features: Device Manager, Control Panel, Explorer, the
Search dialog and more.
5. Find your applications
The
Win+X menu is useful, but no substitute for the old Start menu as it
doesn't provide access to your applications. To find this, hold down the
Windows key and press Q or either right-click an empty part of the
Start screen or swipe your finger up from the bottom of the screen and
select 'All Apps' to reveal a scrolling list of all your installed
applications. Browse the various tiles to find what you need and click
the relevant app to launch it.
If
there's an application you use all the time then you don't have to
access it via the search system. Pin it to the Start screen and it'll be
available at a click.
Start by typing part of the name of your
application. To access Control Panel, for instance, type 'Control'.
Right-click the 'Control Panel' tile on the Apps Search screen, and
click 'Pin to Start'. If you're using a touchscreen, press and hold the
icon, then flick down and select 'Pin to Start'.
Now press the
Windows key, scroll to the right and you'll see the Control Panel tile
at the far end. Drag and drop this over to the left somewhere if you'd
like it more easily accessible, then click the tile to open the desktop
along with the Control Panel window, and press the Windows key to return
you to the Start screen when you're done.
7. Shutting down
To
shut Windows 8 down, just move the mouse cursor to the bottom right
corner of the screen, click the Settings icon - or just hold down the
Windows key and press I - and you'll see a power button. Click this and
choose 'Shut Down' or 'Restart'.
Some of the tricks available in
previous versions of Windows still apply. Press Ctrl+Alt+Del, for
instance, click the power button in the bottom right-hand corner and
you'll be presented with the same 'Shut Down' and 'Restart' options.
And
if you're on the desktop, press Alt+F4 and you'll be able to choose
'Shut Down', 'Restart', 'Sign Out' or 'Switch User' options.
Microsoft today unveiled the “release preview” version of Windows 8
which mostly indicates that the new Windows operating system is
feature-complete. Windows 8 Release Preview is available as a free
download and it is very likely that your existing system specs are good
enough to run Windows 8. The System Requirements for Windows 8
According
to Windows 8 FAQ, any machine equipped with 1 GB of RAM, 16 GB of hard
disk space and 1 GHz processor should be able to handle Windows 8. The
minimum RAM requirements are 2 GB in case you would like to install the
64-bit version of Windows 8. Should you download Windows 8 Setup or the ISO Image?
Update: Where can I Download Windows 8?
As you may have noticed on the Windows 8 download page, the installation of Windows 8 can be done in two ways.
You can either take the easiest route and download the Windows 8 Setup program – that’s also the default option.
Alternatively, you can download ISO Images of Windows 8.
If
you are planning to install Windows 8 on your existing computer, either
on a different partition (dual-boot) or just want to upgrade from an
older version of Windows to Windows 8, the default Setup program is a
good choice.
Please note that that your installed software
programs will only be preserved if you are upgrading from Windows 7 to
Windows 8. If your planning to install Windows 8 on top of Windows XP or
Vista, only the files will be preserved but not the various software
programs that you may have on the disk.
The Windows 8 ISO image may be more handy in other situations like:
Your
computer has an x64 processor but is currently running the 32-bit
version of Windows. If you want to install the 64-bit version of Windows
8, download the 64-bit ISO.
You want to install Windows 8 on your Mac (iMac or Macbook) using Boot Camp software.
You want to install Windows 8 on multiple computers. In that case, you can download the ISO once, create a bootable DVD and boot the other systems using this newly created Windows 8 disk.
You plan to run Windows 8 as a Virtual Machine inside your existing copy of Windows.
You are running Windows XP.
The universal product key for Windows 8 is TK8TP-9JN6P-7X7WW-RFFTV-B7QPF. Will my software programs run inside Windows 8?
Before grabbing the ISO image of Windows 8, quickly run this setup utility
and it will show a list of all software programs and hardware drivers
on your system that are compatible with Windows 8. Alternatively, you
can visit this page to see a list of all known software and hardware devices that are found to be working with Windows 8. How should I go about installing Windows 8?
You can have Windows 8 on your computer in three ways – you can install Windows 8 side-by-side
(also known as dual-boot), as a virtual machine (so that it runs inside
your existing Windows just like any other software) or you can have
Windows 8 as your primary OS (there’s no going back from here).
If you just want to try out Windows 8 but without modifying any of your existing set-up, the safest bet is to use a Virtual Machine.
If you have a vacant disk partition or don’t mind creating one (it’s
easy), go for the dual-boot option. Else, if you have a spare computer,
you can consider upgrading to Windows 8 overwriting the previous installation of Windows.
Also
note that if you are upgrading from Windows 8 Consumer Preview to the
new Windows 8 Release Preview, none of your installed programs, files
and account settings will be preserved though everything would be moved
to the windows.old folder.
