What happened to Double Buffering?

I put in  primitive sort of progress meter into a little Java program
that read a large CSV file [System.out.print(".")]  I was quite
surprised to discover I could easily see the pause when it read the
next buffer full -- synched with the disk light. (Maybe I err. Maybe I
was seeing GCs).

Way way back in the olden days when computers had about 16K and you
coded in assembler, we did double buffering.  In other words, when you
were reading a sequential file, you processed one buffer while the i/o
hardware was filling the other.  This was the NORMAL way of doing
things.  Later, double buffering was built in to COBOL. You got it by
default without writing any code.

Today, when we have RAM coming out our ears we have reverted back to
SINGLE buffering.  We alternate between processing and waiting for I/O
on the same buffer.

What is the matter with us? It is as though we imagine we still have a
single threaded DOS OS.

-- 

Roedy Green Canadian Mind Products
The Java Glossary
http://mindprod.com