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[sindi keesan <keesan AT sdf.lonestar.org>]

> > > Several websites suggested specifying a larger block size than the
> > > default to speed up copying:
> > dd if=/dev/hda of=/dev/hdb bs=8k   - copies in 8k blocks.
> >
> > If you know the sizes of the HD buffers of the two
> > drives, set the bs to the size of the smaller buffer.

1.2GB WDC - 64K.     Conner 540MB 64K.


We just used BL2 ramdisk on hda to clone four partitions from hda to hdb: 
BL2 ramdisk has no hdparm to determine buffer size with, so I just assumed 
all 540MB+ drives had at least 64K buffer size.

First we partitioned and formatted hdc (using pqmagic because my partner 
does not trust linux to do DOS correctly). I would have used BL3 fdisk.

hda is 1.2GB, hdc is 1.0GB, both have three 254MB partitions and one 
larger fourth partition, so I could not do dd if=/dev/hda of=/dev/hdc,
which requires that hdc be at least as large as hda.

dd if=/dev/hda1 of=/dev/hd1
With no block size specified (is the default 1K? - I could hear it 
copying small chunks), took about 6 min on a 233Mhz and used 20-30% 
of cpu time.

dd if=/dev/hda3 of=/dev/hdc3 bs=64k
This took about 3 minutes and used 30-40% of cpu time.

For the fourth drive, I mounted /dev/hdc4 and did a df to learn that it 
had 152104 used 1K blocks.  I could have divided this by 64, but I was 
lazy so typed;

dd if=/dev/hda4 of=/dev/hdc4 bs=1024 count=152104

This copied exactly the number of used blocks, not the whole hda4
(which would not have fit into the smaller hdc4 anyway).

Using 1K block size, it still copied 152MB faster than it did the 
254MB of hda1 at 64K bs.

I did not defragment the partitions first, because we are using DOS7.1 
which only defragments under Windows, and we messed up the file system 
badly one time trying to defragment anyway.  FAT32.

I did not copy the MBR, would I need to if I had not first formatted?

The old 1.2GB drive will now be used for Win98, which we will then clone 
to a 340MB drive from which to copy to 5-10 other computers to give away 
instead of recycling.  Pity nobody wanted linux instead.

Sindi