How to create AWR(Oracle Automatic Workload Repository) Manually

AWR generates an HTML or text view of report which display the statistics about our database for range of snapshot IDs. For creating AWR report open the terminal and connect with oracle user, open sql prompt, run awrrpt.sql script at SQL prompt.
So do the following commands :

Now on the above path you can see all default sql scripts that oracle 11g provide us along with their software. Connect with sqlplus and run awrrpt.sql it will show you the current instance detail.

Now you have to choose format in which you want to create your awr either in html or text.

Genrally snapshots has been taken on some specific performamce related issue by which we can compare two statistics for the same database . We can choose Snap ID when your database will be on peek hours. Below is the list from where you have to chose your Snap ID.

Here you will select your begin and end Snapshot IDs
Then it will prompts for the name of report otherwise it will create default name like awrrpt_1_10407_10609.html.
To use this name,press to continue, otherwise enter an alternative.
This will generate a report into the current folder with "weekend_4th" name

Oracle provide two scripts to produce workload repository reports (awrrpt.sql and awrrpti.sql).
They are similar in format to the statspack reports and give the option of HTML or plain text formats.
The two reports give essential the same output but the awrrpti.sql allows you to select a single instance.
@$ORACLE_HOME/rdbms/admin/awrrpti.sql
@$ORACLE_HOME/rdbms/admin/awrrpt.sql
An example of a HTML AWR report can be seen here.