Windows Tricks: Increase the number of items in Jump Lists

Jump lists are the recent or the pinned items shows when you right click on a particular application in the taskbar.
If you are the person who lean on Jump Items, there may be a time that you have reached the default 10-item in Jump List.
You can increase the number of items in Jump List,
  • Right Click on the taskbar and select properties.
  • Go to Jump List tab
  • Increase the default number of items.

Windows Tricks: Add Locations to Send To menu

  • Create Shortcuts to the folders that you would like to add in “Send To” menu.
  • Type in “shell:sendto” in windows explorer location bar at the top and press enter.
  • You will be taken to a folder. Copy the shortcuts of the folder that you want to add in “Send To” menu.

That’s it ! Right click and check out the new folders added to the menu.

Dive Deep into Oracle DB – Overview of Memory Architecture (2)

The SGA(System Global Area) contains the following data structures:

Database Buffer Cache
The database buffer cache is the portion of the SGA that holds copies of data blocks read from datafiles. All user processes concurrently connected to the instance share access to the database buffer cache. The database buffer cache and the shared SQL cache are logically segmented into multiple sets.

The buffers in the cache are organized in two lists: the write list and the least recently used (LRU) list. The write list holds dirty buffers, which contain data that has been modified but has not yet been written to disk. The LRU list holds free buffers, pinned buffers, and dirty buffers that have not yet been moved to the write list. Free buffers do not contain any useful data and are available for use. Pinned buffers are currently being accessed.

When an Oracle process accesses a buffer, the process moves the buffer to the most recently used (MRU) end of the LRU list. As more buffers are continually moved to the MRU end of the LRU list, dirty buffers age toward the LRU end of the LRU list.

When the user process is performing a full table scan, it reads the blocks of the table into buffers and puts them on the LRU end (instead of the MRU end) of the LRU list. This is because a fully scanned table usually is needed only briefly, so the blocks should be moved out quickly to leave more frequently used blocks in the cache.

Redo Log Buffer

The redo log buffer is a circular buffer in the SGA that holds information about changes made to the database. This information is stored in redo entries. Redo entries contain the information necessary to reconstruct, or redo, changes made to the database by INSERT, UPDATE, DELETE, CREATE, ALTER, or DROP operations. Redo entries are used for database recovery, if necessary.

Redo entries are copied by Oracle database processes from the user’s memory space to the redo log buffer in the SGA. The redo entries take up continuous, sequential space in the buffer. The background process LGWR writes the redo log buffer to the active redo log file (or group of files) on disk.

Shared Pool

The shared pool portion of the SGA contains the library cache, the dictionary cache, buffers for parallel execution messages, and control structures.
The library cache includes the shared SQL areas, private SQL areas (in the case of a shared server configuration), PL/SQL procedures and packages, and control structures such as locks and library cache handles.

The data dictionary is a collection of database tables and views containing reference information about the database, its structures, and its users. Oracle accesses the data dictionary frequently during SQL statement parsing. This is stored in Dictionary Cache.

Large Pool

The database administrator can configure an optional memory area called the large pool to provide large memory allocations for:

  • Session memory for the shared server and the Oracle XA interface (used where transactions interact with more than one database)
  • I/O server processes
  • Oracle backup and restore operations

Java Pool

Java pool memory is used in server memory for all session-specific Java code and data within the JVM. Java pool memory is used in different ways, depending on what mode the Oracle server is running in.
The Java Pool Advisor statistics provide information about library cache memory used for Java and predict how changes in the size of the Java pool can affect the parse rate.

PGA(Program Global Area) contains the following,

Private SQL Area

A private SQL area contains data such as bind information and runtime memory structures. Each session that issues a SQL statement has a private SQL area. Each user that submits the same SQL statement has his or her own private SQL area that uses a single shared SQL area. Thus, many private SQL areas can be associated with the same shared SQL area.

The private SQL area of a cursor is itself divided into two areas whose lifetimes are different:

  • The persistent area, which contains, for example, bind information. It is freed only when the cursor is closed.
  • The run-time area, which is freed when the execution is terminated.

Session Memory

Session memory is the memory allocated to hold a session’s variables (logon information) and other information related to the session. For a shared server, the session memory is shared and not private.

Dive Deep into Oracle DB: Overview of Memory Architecture (1)

Oracle uses memory to store information such as

  • Program code
  • Information about a connected session, even if it is not currently active
  • Information needed during program execution (for example, the current state of a query from which rows are being fetched)
  • Information that is shared and communicated among Oracle processes (for example, locking information)
  • Cached data that is also permanently stored on peripheral memory (for example, data blocks and redo log entries)
The basic memory structures associated with Oracle include:

  • System Global Area (SGA) and
  • Program Global Areas (PGA).

System Global Area

Group of shared memory structures that contain data and control information for one Oracle database instance. If multiple users are concurrently connected to the same instance, then the data in the instance’s SGA is shared among the users.
Contains general information about the state of the database and the instance, which the background processes need to access.This is called the fixed SGA. No user data is stored here.
Includes information communicated between processes, such as locking information.

Program Global Area

Contains data and control information for a server process. It is a nonshared memory created by Oracle when a server process is started. Access to it is exclusive to that server process and is read and written only by Oracle code acting on behalf of it.
Process SQL statements and to hold logon and other session information.
Large part of the PGA is dedicated to SQL work areas and other SQL operations.

About pages in Mozilla Firefox

Mozilla has hidden various configuration and diagnostic information in its internal about pages. Some of the important about pages are ,

1. About:Mozilla
This page contains a verse from the Book of Mozilla.This was first introduced in 1994.
2. About:Config
The contents of this page has already been discussed here.

3. About:Crashes
You’ll find Firefox’s crash reports on the about:crashes page. Click a crash report and it’ll be submitted to Mozilla, where you can view information about it.If you’re struggling with a crash, you can use the information here to figure out what the problem is. Googling up some of the crash messages might help you determine the problem.

4. About:Permissions
Firefox includes website-specific permissions, which you can manage for a single website by right-clicking on a web page selecting View Page Info. About:permissions shows you all this information in one place.

5. About:About
Here you can find all the about pages in Firefox. Try out each one. It will help you to use Firefox efficiently.

Search like a Boss with Firefox

Firefox aids your searches by auto-filling suggested sites based on your bookmarks and browsing history below your search bar.This can be an overwhelming form of assistance particularly if you have many bookmarks and a voluminous browsing history. Fortunately, you can refine this search using the following modifiers

^ for matches in your browsing history
* for matches in your bookmarks
+ for matches in pages you’ve tagged
% for matches in your currently open tabs
~ for matches in pages you’ve typed
# for matches in page titles
@ for matches in web addresses (URLs).

Syntax: <keyword> <space> <modifiers>

Note: You can also use multiple modifiers(with space in between) in same search itself.

Tricks on Google

  • Type “Atari Breakout” in Google Image.
  • Use Google as a Timer. “Set Timer for 19.00”
  • Type “Zerg Rush”,”Tilt”,”do a barrel roll” and “google gravity” and hit the search or feeling lucky button and check what happens.
  • Search for “Google in 1998”, this will take you to the old version of google.
  • Type ‘graph for sin(x)+cos(x)” and check . this will work for all trignometric functions.
  • Find “sunrise and sunset time”
  • Ue google as calculator, tip calculator,currency converter,distance finder and also get details about flight timings.
  • Search for recursion and end up in recursive searches.
  • Try “Solve Circle/Square” or any other shapes and google will help you to solve any Geometric problems