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Wall
12-04-2006, 03:08 AM
Hello.

I have been trying to clone my iBook G4 (1.42 GHz, 512 MB)'s hard drive to my new FW 400 external drive, yet have had to give up because it was taking much longer than expected. I had heard of copying rates of 1 GB per minute, but the copying rate on my computer was only about 0.80 MB/s...
The FireWire transfer rate clearly is not to blame : copying a 500 MB file to the external HD via the Finder only takes a few seconds, as it should.
SD itself does not seem to be the culprit either : I attempted Restoration to my external HD via Disk Utility, with about the same (non-)result...

My questions are :
- Is this copying rate normal given my configuration (a bit outdated, I suppose...) ?
- If not, what can I do to improve it ? Does it have anything to do with the external HD being journaled ?

Thank you in advance for any help.

dnanian
12-04-2006, 08:30 AM
Anything other than the FW drive attached to FireWire? What specific brand/model of drive is it?

Wall
12-04-2006, 09:24 AM
Thanks for your answer.
No, nothing else is attached to the FW port.
My external HD is a 250 GB LaCie d2 with triple interface.
When copying via the Finder, the transfer rate seems to be OK (a few seconds for a 450 MB iDVD project for example). I only seem to have this slowness problem when backing up my entire HD, whether via SuperDuper or Disk Utility.

dnanian
12-04-2006, 10:03 AM
There's certainly a big difference between copying a single very large file (like an iDVD project) and hundreds of thousands of small ones, so it's hard to generalize from Finder's behavior.

So, the overall speed at the end of the copy operation is less than 1MB/s?

Wall
12-04-2006, 10:18 AM
There's certainly a big difference between copying a single very large file (like an iDVD project) and hundreds of thousands of small ones, so it's hard to generalize from Finder's behavior.
I would have thought so.

So, the overall speed at the end of the copy operation is less than 1MB/s?
I made a first clone with the LaCie software included in the device's CD-ROM, and it took most of the night to end up with a buggy clone (no user settings even after permissions were repaired...), which is why I decided to have a go at the widely acclaimed SuperDuper. Unfortunately, when I tried it, I did not have time to wait until the process was finished (had to use the iBook for work), so I stopped it after about 10 minutes, assuming it was going to take as long anyway. My mistake, undoubtedly.
I'll run it tonight in its entirety and post back with the average copying rate.

P.S.: Could the relative slowness of the processor be responsible? It's only a 1.42 GHz G4, but is not 100% active when backing up (according to MenuMeters).

dnanian
12-04-2006, 10:19 AM
In general, a large copying operation is not CPU-bound, it's I/O bound, and is more affected by the speed of that subsystem. If you're running any kind of low-level tool like AntiVirus, though, that'll affect things very severely.

Wall
12-04-2006, 12:52 PM
Thanks again for the answer.
I am running Intego Virus Barrier. Should I start up with extensions disabled before backing up?

dnanian
12-04-2006, 01:03 PM
No, no need. Just turn Virus Barrier's "auto-scan" off.

Wall
12-04-2006, 01:47 PM
No, no need. Just turn Virus Barrier's "auto-scan" off.
Virus Barrier X does not offer this feature, contrary to version X4, so I guess I'll have to go the detour of an extension-free start up.

Wall
12-04-2006, 03:34 PM
Hi Dave,
I started up disabling extensions and launched SuperDuper! For the first few minutes, copy speed was about 2 MB/s, roughly double what it was with extensions (and therefore VirusBarrier auto-scan) active. Excellent tip, thank you!
The speed soon went up, reaching a maximum of ≈7.5 MB/s. Backing up the 22.5 GB took approx. 55 minutes, which is reasonable although longer than the half-hour predicted by some other users.
The cloned volume is fully bootable, with all settings and preferences in place. I'll be working on it for some time just to check that everything's OK.

Before I thank you yet again for making yourself available to answer my questions, I would just like to know if it is possible that subsequent backups be faster, even without SmartUpdate.

Thanks again for great support, and I hope you keep developing this wonderful application in the foreseeable future.

dnanian
12-04-2006, 04:14 PM
7.5MB/s is quite fast for a Power PC based Mac, so that's as good as can be expected for a full copy. Subsequent copies will not go faster without Smart Update, no...

Wall
12-04-2006, 06:13 PM
Fair enough. I'll definitely keep using SuperDuper, probably buying it soon to unlock the advanced settings and Smart Update.