Technical Information
page 27
LaCie Big Disk User’s Manual
5.6. Mac OS Standard vs. Mac OS Extended
There are basically two file systems for the Mac OS: Mac OS Standard (HFS) and Mac OS Extended (HFS+).
Mac OS Standard
Mac OS Standard refers to the file system used by Mac OS 8.0 and earlier. This was the original Hierarchical File System
employed by Apple, and was used before computers really began to see dramatic increases in hard disk drive sizes. In HFS,
the disk is divided into a maximum of 65,536 equal-sized blocks, with these blocks being the destination point of data stored
by the Mac.
Initially, these spaces were small, due to the lack of size in hard drives (i.e. hard drives smaller than 1GB), but as hard drive
space increased, the file system became inefficient. With HFS, even the smallest file on any disk has to occupy at least one
block. For example, if you had a 4GB hard drive and divided it by 65,536, that would equal roughly 64K, and that would
be the smallest block size under HFS. So, if you had a file that was only 4K, it would still have to occupy 64K.
Mac OS Extended
Mac OS Extended refers to the file system used by Mac OS 8.1 and later. HFS+ represents an optimization of the older HFS
file system by using hard disk space more efficiently. As hard disk capacity increased over the years, Apple realized that they
needed to improve the space-saving capabilities of their file system. Building off of HFS, they increased the number of blocks
from 65,536 to 4.29 billion. With HFS+, you are no longer limited by block size. Now, for example, if you have a 4K file, it
will only take up 4K of space.
Guidelines for Choosing Mac OS Standard Or Mac OS Extended
This is actually a fairly easy decision. You should only use Mac OS Standard if you are creating a volume smaller than 32MB,
you are using a Mac with a 680X0 processor or you are creating a file structure that will need to be used by Macs using Mac
OS 8.0 or earlier. Otherwise, you should select Mac OS Extended.
5.7. USB 2.0 vs. FireWire 400 vs. FireWire 800
Trying to decide which interface to use, USB 2.0 or FireWire, can be a complicated decision. Your decision should be based
on the following:
Computer With USB 2.0, FireWire 400 And FireWire 800 Ports
If your computer is equipped with all three interfaces, you have several options to consider. The key decision in this equation
is simple: speed. FireWire 800 effectively offers twice the bandwidth of both USB 2.0 and FireWire 400. So, if you are run-
ning bandwidth-intensive applications, such as digital audio, video or graphics, FireWire 800 is your clear choice.
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