Datamarck:
We took the numbers from each of the benchmarks below and put them into a graph to show you how each setup scores in comparison to each other.
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| Scores shown are MB/s. Higher score is better | Scores shown are access times in milliseconds. Lower is better |
Interesting results when it comes to two drive stripe and four drive stripes where the two drives scored better than the four drives. This may be due to the synthetic benchmark dealing with a small amount of data size which the four drive stripe is not optimized for. The screenshots below are the actual results of each benchmark run. One thing to notice are the plotted graphs. Another point to see notice here is just adding one drive (as oppose to four) to an on-board RAID does make a noticeable improvement in performance, but adding the ADAPTEC 6850E
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| Single Western Digital HDD connected directly to the motherboard via SATA cable. |
The above benchmark is to provide a baseline number for this HDD which is the most common setup in PCs today which are just a single HDD connected to the motherboard.
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| On-board RAID Four Drive Stripe | Adaptec 6850E Four Drive Stripe |
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| On-board RAID two Drive Stripe | Adaptec two drive stripe |
We are using the 6805E controller in a VMWare development setup and it is a reasonably good controller. It would benefit from a bigger cache and the ability to use an SSD for further caching. These are features of other controllers with a considerably bigger price tag though. As it is, the controller does very well on not too random work loads but on purely random IO (like some SQL tasks), it only delivers about 13 mb/s on an otherwise lightly loaded RAID 10 setup. That is not too good. If you are not using VMWare but maybe some Linux setup, you can add your own SSD caching via flashcache (https://github.com/facebook/flashcache/). With a setup like that, you get both redundancy and great performance. On the whole, the controller is certainly preferable to on board SW RAID solutions and such but it could be a lot better too.