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james6000

macrumors member
Original poster
Jul 3, 2007
94
0
UK
I recently purchased a drobo for my macbook. As the macbook only offers firewire 400, what are the speed differences between USB 2.0 and if I was to purchase a firewire 400 to 800 cable?

Thanks
 

micsaund

macrumors 6502
May 31, 2004
364
0
Colorado, USA
FW400 = 400mbits/sec
USB2 = 480mbits/sec

Both of those are theoretical maximum speeds.

FW is a far more advanced interface than USB, so even though USB2 would appear to have an advantage on paper, I'll take FW400 **any day** over a USB2 drive. You'll see lower CPU utilization and overall higher throughput with FireWire due to the intelligent design.
 

Pocket lint

macrumors regular
Sep 2, 2009
112
0
In my trousers
FW400 = 400mbits/sec
USB2 = 480mbits/sec

Both of those are theoretical maximum speeds.

FW is a far more advanced interface than USB, so even though USB2 would appear to have an advantage on paper, I'll take FW400 **any day** over a USB2 drive. You'll see lower CPU utilization and overall higher throughput with FireWire due to the intelligent design.

Yup.

To add to your reply (for the OP):

Firewire has a higher sustained throughput, and unlike USB which utilises the CPU to do the transfers, firewire has its own dedicated chipset so it won't slow your computer down as much.

Also, although this propably doesn't matter in this case (drobo etc.), but USB runs at 5V, whereas firewire runs between 11-25volts, depending on whether it's a laptop or a stationary.
 

james6000

macrumors member
Original poster
Jul 3, 2007
94
0
UK
Thanks.

I've been meaning to do some tests but never got round to it. Its just that recently when transferring large files, my system seems to experience a major drop in performance with mundane tasks. Thought it would be related to firewire, but maybe its just because its handling such large files.
 

pprior

macrumors 65816
Aug 1, 2007
1,448
9
Have you benchmarked with both interfaces?

I get 10-15mb/sec from my drobo using the AJA disk test which is very accurate. at that rate, it doesn't matter usb/fw/fw800 because they all are faster than the device at the end of the cable.
 

pastrychef

macrumors 601
Sep 15, 2006
4,753
1,450
New York City, NY
Have you benchmarked with both interfaces?

I get 10-15mb/sec from my drobo using the AJA disk test which is very accurate. at that rate, it doesn't matter usb/fw/fw800 because they all are faster than the device at the end of the cable.

No, I never did any benchmarks. Unfortunately, the Drobo and Mac mini act as servers and I can't really afford the down time to do benchmarks... But, trust me, it's faster. The Drobo is still no speed demon, but using Firewire makes it more bearable.
 

matthewtoney

macrumors regular
Aug 17, 2009
183
1
Charlotte, NC
I use a Drobo with a FW400 to FW800 cable on a Mac mini. It's considerably faster than USB.

How can you tell? Every benchmark I've ever seen with the Drobo (both the first version and this current one) shows it so slow that it only barely touches the max for USB2 and Firewire 400 both.
 

akm3

macrumors 68020
Nov 15, 2007
2,252
279
How can you tell? Every benchmark I've ever seen with the Drobo (both the first version and this current one) shows it so slow that it only barely touches the max for USB2 and Firewire 400 both.

The transfers won't be any faster (Burst) but sustained will be faster especially if anything else is going on on the computer. Firewire is superior, the cable adapting FW800 to FW400 is cheap (monoprice.com) and it sounds like you aren't using the port anyway.

Go with Firewire.
 

matthewtoney

macrumors regular
Aug 17, 2009
183
1
Charlotte, NC

Gotcha - hadn't seen that. Interesting that it so readily tested better on the firewire stuff, the info I had read for both burst and sustained was so low that I assumed there would be no noticeable difference at all between interfaces.

(I still think the drobo is far too slow for the price they want for it, not that its too fast to make a good backup device, but it certainly doesn't perform like what a device its cost should in my opinion)
 

james6000

macrumors member
Original poster
Jul 3, 2007
94
0
UK
I wouldn't call myself a prosumer, but for use such as editing in lightroom and playing HD content through iTunes, it all runs smoothly. I had one hard drive failure and the process of replacing it was seamless. Very happy with it; albeit at the cost of an arm and a leg!
 

pastrychef

macrumors 601
Sep 15, 2006
4,753
1,450
New York City, NY
Gotcha - hadn't seen that. Interesting that it so readily tested better on the firewire stuff, the info I had read for both burst and sustained was so low that I assumed there would be no noticeable difference at all between interfaces.

(I still think the drobo is far too slow for the price they want for it, not that its too fast to make a good backup device, but it certainly doesn't perform like what a device its cost should in my opinion)

For me, the attractiveness is in it's ability to grow over time by just replacing one drive at a time and the redundancy it affords. By comparison, I also have a NAS that I have configured to a RAID 5 setup. It currently has four 1TB drives. When it fills up and I want to make it bigger, I'll have to find a place to temporarily put all the files, then replace the four 1TB drives with four larger drives all at the same time. On the Drobo, just replace one of the smaller drives with a larger one as your space requirements increase. Also, as time progress, the price of drives also drop, this saves you money. Also, the NAS that I have is actually slower than the Drobo when configured to RAID 5 and that's over gigabit ethernet.

In my opinion, that makes the Drobo just about the perfect device for storage/archival. It is NOT mean to be the scratch disk for Photoshop, etc. Currently, Drobos can often be found at approx $300-$320 which makes it quite competitive to most of the RAID 5 enclosures I've seen. I compare it with RAID 5 enclosures because they offer similar levels of redundnacy and the redundancy overhead is eerily similar.
 
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