February 11th, 2007



Today, I collected my 320GB external disk that I'm planning to use for backups. It supports Firewire 400, and also comes with some actual backup software. So I'm trying it out.

(a) It claims that the Mac has 27-odd GB of data on the disk, which is interesting give that the Mac itself believes it's actually 30-odd GB.
(b) It's been going for just under seven hours now, and it's 9% done.
(c) That means it'll be finished in, oh, a shade under three days, total.

According to Wikipedia, Firewire should have a transfer rate of about 50MB/sec, implying that I should be able to back up 50GB in 1000 seconds, or just over a quarter of an hour. Whereas 9% done seems to work out at a transfer rate of about 0.1MB/sec.

Alternatively, it might be deciding "percent done" by number of files rather than number of bytes, but I'm always wary of backup software whenever there's a root-partition backup going on - it's too easy to just open /dev/whatever and start reading that, and wondering why you never get to the end.

Of course, it's entirely possible I've got the arithmetic completely wrong; it's late, and I'm tired.


Killed it after 8 hours, and 10% (having written 20GB). So it then hung immediately trying to delete said 20GB. Bleh. Went to bed.

I notice it's formatted FAT32 too, which can't be helping...