What is faster to achive to encode 1 chunk of 1mb or 1000 chanks of 1000kb?

[Jabka Atu <mashrom.head@gmail.com>]

Howdy ,...

Im working on encoding system :
it works like that :
reads chank of N bytes use binary operations to show it in log (base 2)  n.

I don't know what is better to use using chanks of 1024^2 bits and  
printing it  as  1k bit output or
to run 1000 encoding functions on 1Kb chunks .

Im asking from the accses to file , and
the cpu.
an example for 8 to 3 is shown here:

http://img228.imageshack.us/img228/458/encodervg1.png

Yours Truly..