[Info-vax] Valid disk types for SIMH?

[Paul Sture]

In article <00832f91$0$1610$c3e8da3 at news.astraweb.com>,
 JF Mezei <jfmezei.spamnot at vaxination.ca> wrote:

> Paul Sture wrote:
> 
> > Now you have me wondering if what I am seeing is a feature of the OS X 
> > file system.
> 
> 
> ls -l  provides the file size in terms of number of bytes used. Not sure
> which incantation of ls s needed to get allocated blocks.

ls -s gives the allocated blocks with a blocksize of 512. This can be 
overridden by specifying a different size via the BLOCKSIZE environment 
variable.

ls -sk gives the number of allocated kilobytes, not blocks. This 
overrides the environment variable BLOCKSIZE.


> when you INIT, i believe that by default, it places some of the
> structures in the middle of the disk.

Thanks. That explains what I am seeing.

> So the container file of say 1 gig would have some structure probably
> written at the start and its middle, but nothing after. So the file
> system would think the logical end of file is the highest byte written,
> hence near the middle of the disk.

A test with

set -L rq3 rauser=100000

$ INIT /INDEX=BEGINNING DUA3: DATA_3

$ ls -s dua3.dsk
1056 dua3.dsk
$ ls -sk dua3.dsk
 528 dua3.dsk

$ INIT /INDEX=MIDDLE DUA3: DATA_3

$ ls -s dua3.dsk
51048 dua3.dsk
$ ls -sk dua3.dsk
25524 dua3.dsk

$ INIT /INDEX= END DUA3: DATA_3

$ ls -s dua3.dsk
99992 dua3.dsk
$ ls -sk dua3.dsk
49996 dua3.dsk

Not quite the full allocation, so:

INIT /ERASE DUA3: DATA_3

$ ls -s dua3.dsk
100000 dua3.dsk
$ ls -sk dua3.dsk
 50000 dua3.dsk

Oh, ls -skl also works:

$ ls -skl dua3.dsk
 50000 -rw-r--r--  1 simh  staff  51199488 Nov 24 16:54 dua3.dsk

FWIW doing an INIT /ERASE on a 30GB disk took about 1 hour 10 minutes on 
my 1.5 GHZ PowerBook. I might play with some FDL file placement to speed 
things up here :-)

-- 
Paul Sture