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Performance on MacBook Pro with Firewire 800
Your best bet is always to get a fast drive inside the MacBook Pro. The MacBook Pro can take two (2) internal drives as an MPG Pro Laptop.
Perhaps in 2011, Apple will deliver a MacBook Pro with some kind of fast external interface, but as of January 2011, the options are extremely limited.
The Firewire 800 results are all limited by aging Firewire 800 technology to mediocre speeds. The very best you can hope for is 84MB/sec, with writes lagging at about 70MB/sec, both speeds well below what even a single hard drive can deliver.
1TB volume limit with Firewire (performance bug)
There is a debilitating Apple performance bug for volumes over 1TB. I first wrote about this bug 3-4 years ago, but Apple apparently will never fix it.
The workaround is to partition the drive. For example, instead of making a single 1.5TB volume as a striped 750+750GB unit, instead make 1TB and 500GB volumes.
The point of this graph is to show just how pitiful Firewire 800 performance is, even with a striped RAID, compared to a single fast internal drive. And how it’s worse for a volume exceeding 1TB in capacity. This is not the fault of the Guardian MAXimus Mini; it’s a Firewire limitation— see the in-depth results further below.
HDD = Seagate Momentus 7200rpm 750GB hard disk drive
Results for combinations of SSD/HDD + eSATA/Firewire 800 + RAID-0/RAID-1.
For performance, use eSATA (available only with MacBook Pros having an ExpressCard/34 slot).
For convenience of powering and cabling, use Firewire 800, and keep volume size no larger than 1TB.
Forget about USB 2.0 except in an emergency.