The second chart shows the number of seconds taken to uncompress the file. I sourced the tar from a separate disk so that the external enclosure was only writing at the time. Given that the Xbench scores were questionable (the numbers indicated a five-fold performance of ZFS over HFS), I used a different metric - timing how long it took to untar an uncompressed version of Eclipse 3.4M6a, which is a 147Mb file untarred (around 170Mb on disk with just over 1000 files), and is a reasonable test of sustained writing. For the HFS RAID case, I used Mac's built-in RAID support to create the mirror for ZFS, I used ZFS' mirroring capabilities to do the work. These were tested using two different set-ups one in which the drive was used in a singe-drive mode (aka JBOD), and the other with a mirrored-drive mode (aka RAID). Needless to say, buying a drive with both USB and FireWire is a sensible choice because then you can decide for yourself which is the sensible interface to use. In fact, the performance of FireWire 400 with mirrored RAID was faster than accessing the USB 2.0 drive without RAID it's that noticable a difference. To verify that this wasn't an issue with one machine, the same test was repeated with a PowerBook G4 laptop and the results indicated that the FireWire 400 was about twice as fast as the USB 2.0 was for punting data. What may be surprising to some is the relatively poor performance of USB 2.0 even though it has a higher rated notional top-speed to FireWire 400, the actual performance seen over the USB is much less than the corresponding FireWire port is. Unsurprisingly, FireWire 800 wins as the highest performing interface but it's not twice the speed of FireWire 400, presumably because the interface can pump data faster than the hard drives can access it. It's not particularly relevant to compare the numbers directly, but rather, the relative performance between the two.
![xbench 1.3 xbench 1.3](https://pic2.zhimg.com/v2-82470a4d9c398d155da77aac5ce6f64f_r.jpg)
Numbers are Xbench disk scores higher is better. The results for ZFS and Xbench were questionable, so I'm just comparing HFS+ over the interfaces using a JBOD and RAID approach. For each interface, tests were run using HFS+ and ZFS on a single disk (JBOD), and in a mirrored (RAID) configuration.
#Xbench 1.3 for mac#
Tests included XBench 1.3 on the disk test and extracting Eclipse 3.4M6a SDK for Mac from an uncompressed tar file to test write performance and calculating the md5 signature across all files to test read performance.
![xbench 1.3 xbench 1.3](https://img.creativemark.co.uk/uploads/images/168/13168/largeImg.jpg)
Whilst the tests were running, no other processes or applications were running. In each case, the drive was connected directly to the computer (no hubs) and System Profiler confirmed that it was using the appropriate speed. Testing was done on a PowerMac G5 with 3G of memory and using the Iomega Ultramax as an external drive across the USB 2.0 bus, FW 400 bus, and FW 800 bus. If you want a mirrored RAID setup, then ZFS is the right way to go. Anyone who is considering an external drive for Mac use should not seriously consider buying a USB 2.0 drive under any circumstances (not least because of problems with USB drives reported earlier). The conclusion is that FW 400 beats USB 2.0 by a significant margin, and that FW 800 (if you have it) gives a marginal edge over FW 400. In addition, the 1TB is made up of two 0.5TB disks which can be configured as one large disk, two 0.5TB disks, one 0.5TB mirrored array or one 1TB striped disk. The advantage of this model is that it's a triple-interface USB 2.0, FW 400 and FW 800, so I could compare the relative merits of each interface and the performance of the drive in general. What can be gathered from tis is to run your test under "real world" situations, don't shut off or unhook anything.I recently purchased an Iomega Ultramax 1 TB external drive to build a ZFS partition on. I decided to run the test under actual everyday use, just restarted, didn't shut anything off, attached my external drives and tested.
![xbench 1.3 xbench 1.3](http://alexnat.de/resources/images/content/gfx_update-4.jpg)
Interesting, I had printer sharing, internet sharing on and it didn't seem to impact the overall scores, I also had dashboard on and disabled for some.didn't really seem to impact. Uncached Readđ51.01Ē8.02 MB/sec Īfter running the test under several different parameters, I found this to be average, sometimes scoring higher or lower, sometimes with programs running or not, sometimes external USB (original HD) attached.
![xbench 1.3 xbench 1.3](https://image.itmedia.co.jp/pcuser/articles/1111/24/og_thunder_020.jpg)
Wd Scorpio Black, 7200 RPM 16mB Cache 320 GB