smartdrv cdrom cache

[T. Ment]

If you load mscdex first, smartdrv will cache the cdrom. To save memory,
I reduced the smartdrv read ahead size. It defaults to 16k, I set it to
8k.

But when I installed software from cdrom I got data corruption. When I
went back to smartdrv defaults the problem disappeared. Seems the cdrom
caching fails when read ahead size equals element size.

It worked when I reduced both, keeping the 2 to 1 ratio. There is some
performance loss. Not big, but not wanted either.

At least now I know how to work around the problem. shsucdx has it too.
So it must be a smartdrv bug.