printing & BogoMips

[Markus Nullmeier]

In article <26n50a$j...@kruuna.Helsinki.FI> Lars Wirzenius (wirz...@kruuna.Helsinki.FI) writes:
> BogoMips are Linus's invention. The kernel (or was it a device
> driver?) needs a timing loop (the time is too short and/or needs to be
> too exact for a non-busy-loop method of waiting)

The cheap QIC-80 hardware reportedly needs such strange methods of timing.

--
---------------------------------------------------
Markus Nullmeier af...@ix.urz.uni-heidelberg.de

[Tim Lacy]

Two completely unrelated questions:

1. I have not been able to get lpr,lpd,etc to work right.
/usr/spool/lpd
/usr/spool/lp1
/dev/lp1 is linked to /dev/printer ( actually, the reverse is true )
lpd starts and stays running from my rc.local script
lpc says all is well, things get queued, no daemon present
lpc start, stop, up, down all produce expected results, except for the
'no daemon present' comment.

I have tried everything I've read here to get it to work. I can call:
print /etc/gettydefs
and ir works just fine, but nothing gets printed with
lpr /etc/gettydefs

Any more hints?

2. What is a BogoMip? My compiles ( kernel) take forever.
I have a 386DX33 with 16 Mb, two 210 Mb IDE Drives, two 10 Mb swaps.
And of course, '5.86 BogoMips' - is this a reasonable number?

Thanks,

--Tim
<ti...@microsoft.com>
<ti...@cyberspace.com>

[Lars Wirzenius]

ti...@microsoft.com (Tim Lacy) writes:
> 2. What is a BogoMip?

MIPS is short for Millions of Instructions Per Second. It is a
measure for the computation speed of a program. Like most such
measures, it is more often abused than used properly (it is very
difficult to justly compare MIPS for different kinds of computers).

BogoMips are Linus's invention. The kernel (or was it a device
driver?) needs a timing loop (the time is too short and/or needs to be

too exact for a non-busy-loop method of waiting), which must be
calibrated to the processor speed of the machine. Hence, the kernel
measures at boot time how fast a certain kind of busy loop runs on a
computer. "Bogo" comes from "bogus", i.e, something which is a fake.
(See the Jargon File for more information.) Hence, the BogoMips value
gives some indication of the processor speed, but it is way too
unscientific to be called anything but BogoMips.

The reasons (there are two) it is printed during bootup is that a) it
is slightly useful for debugging and for checking that the computers
caches and turbo button work, and b) Linus loves to chuckle when he
sees confused people on the news.

> My compiles ( kernel) take forever. I have a 386DX33 with 16 Mb,
> two 210 Mb IDE Drives, two 10 Mb swaps. And of course, '5.86
> BogoMips' - is this a reasonable number?

My machine is 386DX33, 8 MB, 64 kB memory cache, 109 MB IDE, 12 MB
swap partition, about 5.99 BogoMips. I think your BogoMips sound
reasonable.

What is "forever"? My kernel compiles take around 20 min (depending
on configuration options), when not running anything else (i.e., no
X). If yours are significantly slower, there might be something wrong
in your setup. Are your swaps files or partitions? Partitions are
much faster.

--
Lars.Wi...@helsinki.fi (finger wirz...@klaava.helsinki.fi)
MS-DOS, you can't live with it, you can live without it.