Newsgroups: comp.os.minix
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Large Disks
Message-ID: <1989Oct8.023413.12467@utzoo.uucp>
Organization: U of Toronto Zoology
References: <241@vsserv.scri.fsu.edu> <3491@ast.cs.vu.nl> <2988@ndsuvax.UUCP> <3541@ast.cs.vu.nl>
Date: Sun, 8 Oct 89 02:34:13 GMT

In article <3541@ast.cs.vu.nl> ast@cs.vu.nl (Andy Tanenbaum) writes:
>>I think it would also be very useful to be able to SET the disk geometry
>>parameters in the driver with the ioctl
>
>Ioctl really isn't for disks.  It would be best if the driver could figure
>out the geometry itself...

The reason for the switch from gtty/stty to ioctl was the observation that
such operations were useful for more than just ttys.  Yes, I have seen disk
drivers with ioctls; in fact, I've written one.  (Being able to set tuning
parameters without recompile/reboot enormously speeded up some experiments
with said parameters, and the result was a doubling of disk throughput.
It's also a much better way to read disk-usage statistics than grubbing
through /dev/kmem.)
-- 
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry henry@zoo.toronto.edu