Linode uses SAS drives (i'm guessing RAID-10), which from my testing, performs marginally better than commodity SSD drives which I believe DO are using. I don't think it's even an Intel 520.
The study indicates to me DO also may be SSD's on SAN or network drives, which is good for their scalability but bad for performance (think EC2).
Linode on the other hand is Direct Attached, similar to Rackspace Cloud (but they don't use SAS which are 15k5 RPM where as regular SATA drives are 7200RPM).
It's hard to beat a DAS RAID-10 SAS for performance and reliability. If DO offered a DAS RAID-10 SSD, then I'm sure their $5/month plan would increase to atleast $30/month.
If DO really wants to be the coolest kid on the block, they should offer DAS RAID-10 Intel S3500 SSDs and offer it for $5/month on a Ivy Bridge Intel E5-26xx's. Now that'll blow away the competition for sure. :D But that setup would atleast cost $100/month for perhaps 20gb of data.
LOL. Fast SCSI spinning disks are 200 IOPS. If you RAID 10 of them then you get 2000 IOPS.
Consumer SSDs are now at 50-100K IOPS. How on earth do people think that 2000 IOPS is "marginally better" than 50000? And I am just comparing one SSD to a RAID array.
I think you just must be completely unaware of random access disk performance and the massive disparity there.
The results were close because either the Linode host he was testing on actually had SSD storage or more likely because of some caching which indicates that the benchmark did not actually test random reads or writes or seeks.
SAS is an interface, not a type of drive. You can get SSD drives with SAS interface easily.
You also write "SAS which are 15k5 RPM", but SAS does not dictate rotational speed (nor, as mentioned, that the drives use spinning platters at all). They are usually higher RPM if they are regular hd's as it doesn't make much sense to buy SAS controllers and SAS drives if you're going to opt for cheap consumer level performance. But my usual source of drives have both 7200 rpm and 10k RPM SAS drives.
Spending on SSD's for SAN/NAS storage would make absolutely zero sense unless your connectivity to said SAN/NAS is extremely low latency and high throughput - it'd be like burning money, so I very much doubt that's the bottleneck.
Linode on the other hand is Direct Attached, similar to Rackspace Cloud (but they don't use SAS which are 15k5 RPM where as regular SATA drives are 7200RPM).
It's hard to beat a DAS RAID-10 SAS for performance and reliability. If DO offered a DAS RAID-10 SSD, then I'm sure their $5/month plan would increase to atleast $30/month.
If DO really wants to be the coolest kid on the block, they should offer DAS RAID-10 Intel S3500 SSDs and offer it for $5/month on a Ivy Bridge Intel E5-26xx's. Now that'll blow away the competition for sure. :D But that setup would atleast cost $100/month for perhaps 20gb of data.
TLDR: You get what you pay for.