| Title: | DIGITAL UNIX (FORMERLY KNOWN AS DEC OSF/1) |
| Notice: | Welcome to the Digital UNIX Conference |
| Moderator: | SMURF::DENHAM |
| Created: | Thu Mar 16 1995 |
| Last Modified: | Fri Jun 06 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 10068 |
| Total number of notes: | 35879 |
Hi all, Has anyone noticed that the conversion from blocks to Megabytes is wrong on the "diskconfig" utility in DU V4.0. Thus if you work in Megabytes and commit your configuration. Then look at the disklabel your partitions will be about 5% smaller than you wanted them. Cheers Lance. [Posted by WWW Notes gateway]
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 9030.1 | Some people think 1 = 1.048576 | SMURF::KNIGHT | Fred Knight | Tue Mar 04 1997 18:21 | 26 |
Oh NO, marketing does it again. This is probably the old computer Mega-bytes vs. Marketing Mega-bytes. Marketing Mega-bytes is also known as Metric Mega-bytes. Does a Mega-byte = 1 Million bytes = 1,000,000 bytes? or Does a Mega-byte = 1 Million bytes = 1,048,576 bytes? If you are familiar with the real world of Kilometers and Kilograms and all those other measurements for length, and mass, and all that other stuff, then you might assume that 1 million = 1,000,000. If you also assume that 1 character = 1 byte, then a disk with room for 1 million bytes should store a 1,000,000 character document. Notice that most (if not all) disk vendors use the marketing Mega-byte for the measurement for their disks. A 135Mb disk I have will hold a document containing roughly 135,000,000 characters (or bytes). It actually holds exactly 134,217,728 bytes (which if you divide by 1048576 - a computer mega-byte, makes 128Mb). So, I guess that just goes to prove that in marketing 128 = 135 (or 1 = 1.048576). I suppose it's a miracle that marketing people and computer people ever agree! Fred | |||||
| 9030.2 | DECWET::MARTIN | Tue Mar 04 1997 18:42 | 11 | ||
And if you want to get even more confusing than 1,000,000 == 1048576, then take
a look at 3 1/2 inch floppy disks. You know, the standard floppy disk of today,
which holds "1.44 MB"? Well, it will actually hold 1474560 bytes.
Lessee, 1474560 / 1000000 = 1.47 MB. Nope, that ain't it.
1474560 / 1048576 = 1.41 MB. Nope, that ain't it either.
1474560 / 1.44 = 1024000.
That's right, a "floppy disk megabyte" is 1024 * 1000. Somebody decided to
combine the 2^10 and the 10^3 figures. Aieeee!
| |||||
| 9030.3 | Will be fixed | NETRIX::"chip@diamond.unx.dec.com" | Chip Maurer | Fri Apr 04 1997 16:04 | 6 |
Yes. The conversion of blocks -> megabytes is wrong in 4.0 version of diskconfig. This will be fixed in 4.2 (Steel) release, as well as a significant change to the interface. [Posted by WWW Notes gateway] | |||||
| 9030.4 | SMURF::DENHAM | Digital UNIX Kernel | Fri Apr 04 1997 17:19 | 2 | |
Come on! Fix it in V4.0D. Why wait almost a year for Steel! We have
a real development release open now....
| |||||
| 9030.5 | You're right | NNTPD::"chip@diamond.unx.dec.com" | Chip Maurer | Wed Apr 16 1997 17:31 | 7 |
Up to now, my emphasis on diskconfig had been Steel. I've been going over the QARs and will work on getting as many QAR fixes into 4.0D as I can (including the megabyte fix). [Posted by WWW Notes gateway] | |||||