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View Full Version : mac mini internal drive vs usb-2 vs firewire-400


Fastfwd
03-09-2007, 12:07 PM
I have all of those connected at once so I was able to run some very quick and informal tests. I'm not accounting for any CPU saturation/use.

It seems that usb 2 will run at approx 12MB/s
Both internal and firewire run around 20MB/s with firewire being a little faster overall.

Was it worth it to get a firewire drive? For my needs probably not but if you find yourself waiting for file loads/transfers/changes it's probably worth it.

I use mine to put on music and movies. the usb 2 is a backup drive. I could have gotten 2 usb drives and same some money and see no difference.

trevor
03-09-2007, 12:25 PM
The internal drive in a Mac Mini is an inexpensive 2.5" drive. If you buy an external FireWire 3.5" drive, it should be much faster than 20 MB/s. Depending on drive, I'd say somewhere between 40 and 55 MB/s on FireWire 400.

Trevor

Fastfwd
03-09-2007, 12:28 PM
I'll run some more tests then. The drive I have is a western digital mybook pro. I'm pretty sure it'S a 3.5" 7200rpm. It does both firewire-800 and 400 but I only have 400 to test it with.

Is there a chart somewhere on firewire bandwidth?

Fastfwd
03-09-2007, 12:50 PM
Yup I seem to be running into CPU issues. I'll try to clean up my system and run those again. But it still shows that no matter how fast you drive is, it's worthless if the interface is eating up all your cpu.

trevor
03-09-2007, 01:03 PM
Is there a chart somewhere on firewire bandwidth?

Go to Barefeats http://barefeats.com and look at the speed tests there for various hard drives, external and internal.

Trevor

Fastfwd
03-09-2007, 01:08 PM
Good link. Thanks.

According to this http://barefeats.com/5472.html they are seeing 38 on sustained reads with firewire-400 on a macbook pro. I am now seeing 35 using only one disk for sustained reads.

I guess it depends a lot on what exactly you are doing but I definitely won't reach the theoretical limit of 50 for firewire 400.

styrafome
03-09-2007, 01:19 PM
On my own systems, the data rate is much slower when copying more smaller files, and closer to the theoretical limit when copying fewer, larger files. Probably because of overhead.

USB should cause more CPU overhead because of its design. FireWire's design is decentralized and does not requires a CPU (though the OS X implementation might), so in theory if you want less load on your CPU you should avoid USB.