back up speed

[Christian Tanner]

so - i'm backing up a cf-card to an external hd via mac book pro - and get a data rate of roughly 11MB/sek (8gb fc - so about 7,3GB - in 10min. 57sek.). seems pretty slow to me, so i thought i'd ask those experienced DIT's out there what it is that i'm doing wrong...


flash card is a lexar 300X udma.
card reader is a lexar pro udma firewire 800
portable hard drive is a western digital "my passport", 5400rpm, 320gb, firewire 800.
i'm using r3d data manager.
i'm using the firewire 800 port to connect from card reader to the mac book pro.
i'm using the firewire 400 port to connect from mac book to portable hd. (express card to get a couple extra firewire 800 ports not here yet...)


any ideas?
what throughputs/data rates do you guys get, when you back up on set? (how long does it take you to back up an 8gb fc)?

many thanx in advance!

[Roberto Lequeux]

I would use something like HDtach to test both the card and HDD to find the bottleneck.

http://en.wikipedia.org/wiki/HD_Tach

[Conrad Hunziker]

You'll get better rates when you:

- dont use firewire 400
- dont use the same bus for transferring
- use a faster destination drive

Our testing shows rates at least 4 to 6 times what you are getting. We use eSATA to transfer to. You can see your actual transfer rates in real time using activity monitor.

[Brent J. Craig]

Those WD portable drives are verrry slow. Also, as mentioned both firewire ports on the macbook use the same data bus.

I find it faster to transfer to the internal hard drive then back out to a portable.

[Christian Tanner]

thanx guys!

so - conrad - you probably connect your hd's by expresscard/esata right? (like the tempo sata express card from sonnet).

what card reader do you use? i didn't find an esata one. (i found an express compact flash card though).

i ralize a 7200rpm or even 10000rpm drive would perform better - but a 5400rpm drive still doesn't explain the slow data transfer as it should give me around 30MB per second.
what portable drives do you guys use?

[Christian Tanner]

brent - that makes sense - but my DIT would have to run off-set to the dit-station a second time that way. not the most economical approach i'd say, don't you think?

[Brent J. Craig]

i ralize a 7200rpm or even 10000rpm drive would perform better - but a 5400rpm drive still doesn't explain the slow data transfer as it should give me around 30MB per second.

There is something abnormally slow about the interface electronics in the passport drives. I broke one open and used the drive inside to upgrade my Macbook's internal drive and it is faster than the original from Apple. I don't know why the little interface board that connects to USB or Firewire is so slow, but the slowdown is not from the drive itself.

[Christian Tanner]

so - what hd DO you use then?

[Roberto Lequeux]

I agree about WD externals as a whole being slow. I have a WD 2 x 7200rpm that gives me about 70MB as RAID1 and only 100MB as RAID0. My guess is that they use the cheapest components for those.

[Christian Tanner]

i tried to stay away from raid0 so far as i see it as a way of getting twice the speed for twice the possibility of failure...
..and raid4 sounded too bulky for on-set use.
(but if speed doesn't improve with the express card option i might look into an f2 fusion nevertheless...)

so again - i'm curious on what set-ups you use for cf cards and how fast you guys back up.