[IMFORMATION]What is SWAP

Today i want to give imformation about what is SWAP

Now first we know What is RAM?
Random Access Memory (RAM) is
temporary data storage that the CPU
uses during calculations. The more RAM
a device has, the more calculated
results the CPU can store - which
means less time the CPU has to do the
same thing over and over again. In
other words, the CPU can check RAM
to see if it has already made a
particular calculation in the recent
past. If it has, it can use the pre-
computed results instead of wasting
processing time recomputing the same
calculation. In short, more RAM means
a more efficient (and faster) device.

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WHAT IS SWAP?
Swap is, in short, virtual RAM. With
swap, a small portion of the hard drive
is set aside and used like RAM. The
computer will attempt to keep as much
information as possible in RAM until the
RAM is full. At that point, the computer
will begin moving inactive blocks of
memory (called pages) to the hard disk,
freeing up RAM for active processes. If
one of the pages on the hard disk
needs to be accessed again, it will be
moved back into RAM, and a different
inactive page in RAM will be moved
onto the hard disk ('swapped'). The
trade off is disks and SD cards are
considerably slower than physical RAM,
so when something needs to be
swapped, there is a noticeable
performance hit.
Unlike traditional swap, Android's
Memory Manager kills inactive
processes to free up memory. Android
signals to the process, then the process
will usually write out a small bit of
specific information about its state (for
example, Google Maps may write out
the map view coordinates; Browser
might write the URL of the page being
viewed) and then the process exits.
When you next access that application,
it is restarted: the application is loaded
from storage, and retrieves the state
information that it saved when it last
closed. In some applications, this makes
it seem as if the application never
closed at all. This is not much different
from traditional swap, except that
Android apps are specially programed
to write out very specific information,
making Android's Memory Manager
more efficient that swap.