Sustained Transfer Speed — OWC 480GB 6G SSD on 2010 Mac Pro 3G Ports

The 480GB OWC Mercury Extreme Pro 6G SSD is a 6 Gbps SATA device, but it can be put to very productive use on the 2009/2010 Mac Pro, even though those machines have 3 Gbps SATA ports.

Show below are graphs for a single SSD, and also RAID-0 stripes of 2 and 3 SSDs.

Note in the graphs below the vertical axes changes scale to accommodate the higher speeds for 2 and 3 drives in a RAID-0 stripe.

Single SSD

For compressible data, excellent performance that is about as high as SATA 3G goes with any SSD for this test.

Speed for incompressible data drops off substantially for writes to about 175 MB/sec, but in the real world performance tends to be outstanding, and the read speed is unaffected.

Single SSD on Mac Pro 3G SATA port
DiskTester fill-volume with OWC Mercury Extreme Pro 6G SSD 480GB

Dual SSD RAID-0 stripe

Excellent scalability to two SSDs as a RAID-0 stripe.

Dual SSD RAID-0 stripe on Mac Pro 3G SATA ports
DiskTester fill-volume with OWC Mercury Extreme Pro 6G SSD 480GB

Triple SSD RAID-0 stripe

I’ve never before seen read speeds of 750MB/sec in the 2010 Mac Pro with any drives on the internal SATA ports— impressive. If usage requires very high read speeds and still very high write speeds, a triple-SSD stripe looks like the killer solution on the internal ports.

Excellent scalability for reads, but the Mac Pro internal SATA bus appears to impair the write speed, which is typical, no matter what type of drive is used.

Triple SSD RAID-0 stripe on Mac Pro 3G SATA ports
DiskTester fill-volume with OWC Mercury Extreme Pro 6G SSD 480GB