The External Hard Drive Post at Josh Kim dot Org

I needed a hard drive. Instead of going all out and getting a single 1TB storage, I went for a 500 GB instead.

Firewire is amazing for external hard drives. It’s a little bit more expensive then the single USB 2.0 options, but man… it’s a lot faster.

Plus, you really can’t buy external drives with just FireWire anymore. Usually. FireWire drives just come with USB anyway, so you’ve got some backward capability.

Yes, I just called USB 2.0 “backwards”. You’ll see why in a second.

tan ( ) : Firewire, USB 2.0 Comparison

From the site: FireWire - USB Comparison

FireWire is faster than USB 2.0 in sustained throughput.

Read Test:

5000 files (300 MB total) FireWire was 33% faster than USB 2.0
160 files (650MB total) FireWire was 70% faster than USB 2.0

Write Test:

5000 files (300 MB total) FireWire was 16% faster than USB 2.0
160 files (650MB total) FireWire was 48% faster than USB 2.0

USB 2.0: Needs a master and a slave. Peripherals are dumb. FireWire 400: Peer-to-peer. Peripherals are intelligent.

Back to the rest of the post: The Pipes

Here are some random numbers, for your pleasure.

Now, mind you, these are theoretical limits of the pipe. Doesn’t say anything about how fast the devices are running themselves. (Hooray for CS 423 - Operating Systems, this class should be required.)

Right, so how fast does a 7200 RPM 16 MB Cache hard drive read and write? This largely depends on burst and sustained… Seek time is less than 10ms… How far radially is the data stored…

I wasn’t able to figure this out. If someone can give me actual numbers, I’ll be very appreciated. So instead, I decided to run some tests.

Even better. Actual real world tests.

Using Xbench

Internal Hard Drive (SATA)

Results 37.67   
    System Info     
        Xbench Version      1.2
        System Version      10.4.11 (8S2167)
        Physical RAM        2048 MB
        Model       MacBookPro3,1
        Drive Type      FUJITSU MHW2160BHPL
    Disk Test   37.67   
        Sequential  59.52   
            Uncached Write  69.06   42.40 MB/sec [4K blocks]
            Uncached Write  64.01   36.22 MB/sec [256K blocks]
            Uncached Read   41.65   12.19 MB/sec [4K blocks]
            Uncached Read   76.38   38.39 MB/sec [256K blocks]
        Random  27.56   
            Uncached Write  9.86    1.04 MB/sec [4K blocks]
            Uncached Write  62.81   20.11 MB/sec [256K blocks]
            Uncached Read   59.29   0.42 MB/sec [4K blocks]
            Uncached Read   91.63   17.00 MB/sec [256K blocks]

FireWire 800

Results 51.81   
    System Info     
        Xbench Version      1.2
        System Version      10.4.11 (8S2167)
        Physical RAM        2048 MB
        Model       MacBookPro3,1
        Drive Type      ST350063 0AS
    Disk Test   51.81   
        Sequential  83.84   
            Uncached Write  68.96   42.34 MB/sec [4K blocks]
            Uncached Write  99.59   56.35 MB/sec [256K blocks]
            Uncached Read   60.13   17.60 MB/sec [4K blocks]
            Uncached Read   152.93  76.86 MB/sec [256K blocks]
        Random  37.49   
            Uncached Write  12.78   1.35 MB/sec [4K blocks]
            Uncached Write  94.76   30.34 MB/sec [256K blocks]
            Uncached Read   91.12   0.65 MB/sec [4K blocks]
            Uncached Read   144.77  26.86 MB/sec [256K blocks]

What the heck is going on? How the heck is my external outperforming my desktop in every single possible way?

EDIT: I had forgot to think about the RPMs. Since laptops are design for lower power consumption, normally they come with 5400 RPM drives instead of 7200 RPM, which is the one that’s in the external. Now these numbers make sense.

For fun, I performed the test for FireWire 400 and USB 2.0.

FireWire 400

Results 44.61   
    System Info     
        Xbench Version      1.2
        System Version      10.4.11 (8S2167)
        Physical RAM        2048 MB
        Model       MacBookPro3,1
        Drive Type      ST350063 0AS
    Disk Test   44.61   
        Sequential  59.75   
            Uncached Write  53.08   32.59 MB/sec [4K blocks]
            Uncached Write  64.79   36.66 MB/sec [256K blocks]
            Uncached Read   50.22   14.70 MB/sec [4K blocks]
            Uncached Read   78.36   39.38 MB/sec [256K blocks]
        Random  35.59   
            Uncached Write  12.97   1.37 MB/sec [4K blocks]
            Uncached Write  65.63   21.01 MB/sec [256K blocks]
            Uncached Read   91.10   0.65 MB/sec [4K blocks]
            Uncached Read   109.82  20.38 MB/sec [256K blocks]

USB 2.0

Results 16.61   
    System Info     
        Xbench Version      1.2
        System Version      10.4.11 (8S2167)
        Physical RAM        2048 MB
        Model       MacBookPro3,1
        Drive Type      ST350063 0AS
    Disk Test   16.61   
        Sequential  12.73   
            Uncached Write  30.12   18.49 MB/sec [4K blocks]
            Uncached Write  31.23   17.67 MB/sec [256K blocks]
            Uncached Read   4.45    1.30 MB/sec [4K blocks]
            Uncached Read   41.40   20.81 MB/sec [256K blocks]
        Random  23.89   
            Uncached Write  8.47    0.90 MB/sec [4K blocks]
            Uncached Write  44.95   14.39 MB/sec [256K blocks]
            Uncached Read   69.71   0.49 MB/sec [4K blocks]
            Uncached Read   78.19   14.51 MB/sec [256K blocks]

Here’s a simple table output of this data.

Table of Hard Drive Test Data

~~In a real world test, an External FireWire 800 connection somehow managed to beat my Internal SATA drive. Again, if someone could possibly explain this data, let me know.~~

EDIT: Once again, I realized the error I made: Here, I thought for some reason that the internal drive had similar specs as the external. I also have a feeling that the buffer size is going to be different also due to the size difference (8 MB for internal, 16 MB for external).

Conclusion

In the end, I’m glad I made the switch to FireWire. Now all my Time Machine backups are faster, and requires less strain on the Core 2 Duo processors.

I really hope, though, that the next external data source I purchase will be a part of the Cloud… you know, the ones where I don’t have to deal with the physical media at all. No disks, no CDs, no DVDs, not even Hard Drives: Just some made up blocks of data storage somewhere.

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