Kernel Configuration Part XV

Kernel Configuration - Part XV

We’re moving along in the kernel configuration series. The guiding ideology in
this series has been to pick apart each section of the kernel configuration
routine, spending some time discussing the importance of each. Today’ we’ll take

that approach with the ATA/IDE/MFM/RLL support section.

Of all the revolutions in computers over the past ten years, none has been as
far-reaching as the decreased cost of manufacturing individual components. We’ve

seen it in processor costs, RAM costs and, relevant to today’s GnomeCORE,
storage costs.

Sixteen years ago, my first computer purchase (an Atari 1040ST) had no internal storage. A 3.25″ floppy or two

covered all the storage needs. You could, of course, add an external hard drive
- 250 Mb at around $2000 - more than the entire computer cost new.

So what was the revolution that brought about affordable high-capacity drives?
The invention of Integrated Disk Electronics (IDE) by Western Digital and Compaq

in 1984. AT Attachment (ATA) is a superset of the IDE specification for the
storage device interface. IDE and ATA (now ATA Packet Interface, or ATAPI) made
it possible to manufacture low cost drives that could be built directly into the

computers and would transfer data at an acceptably quick rate. Revisions to the
standards now mean that most hard drives purchased are, in fact, EIDE drives
(Enhanced IDE) that have high storage capacity and can contain many more
physical disks than the original IDE standard. For mass manufacturing, EIDE has
become the hard drive standard and ATAPI has become the de facto standard for
CD-ROM drives.

That said, SCSI (Small Computer System Interface) architected drives are still
available. In fact, they’re the choice of system admins running machines in a
business environment where redundancy and reliability are mission critical. They

are, in many ways, the Cadillacs of storage. Of course, that’s also reflected in

the pricing.

If your home Linux machine is using IDE/ATAPI storage devices, you’ll need to
configure this support into your kernel. The choice to build the drivers
directly into the kernel or as loadable modules is always your own. If, on the
other hand, you’re using SCSI-interfaced storage devices, you’re safe to ignore
the ATA/IDE/MFM/RLL configration altogether.

And, what do you know? Tomorrow, we’ll talk about configuring your kernel to
support SCSI devices.