Originally Posted by sevilnatas
So anyone ever actually get their hands on an actual SAS expander card and try it out? They almost seem like things of myth and legend. I am dying to get a few but don't want to go and spend the money to be the first to find the compatability problems. I can't really afford to take one for the team like that.
Wish I could...
According to my e-mail from provantage, they received the expander at their ohio warehouse and are in process of forwarding it to my address. It's the 28 port chenbro expander. I plan to test it with my adaptec 51645 and 31605 cards. I'd test it with more cards, but those are the only SAS cards I have. I'm gonna lay off getting any new cards for evaluation as SAS-2 6GB/s is right around the corner, and I suspect vendors will be coming out with new SAS-2 HBAs and RAID cards this coming year, e.g. LSI Logic and Adaptec.
There's a white paper over on the LSI page expounding on the benefits of SAS-2, and they did a little comparative graph of their SAS vs SAS2 performance results - it looks like their write speeds improved tremendously, so if they come out with a new RAID card, I might pick that up to replace my adaptec. It looks like ATTO already has some SAS2 HBAs available, but only available for OEMs.
Looks like Seagate is coming out with new SAS2 drives as well, e.g. the next generation Cheetahs and Savvios, with higher STR. I'm still not convinced of the long term reliability of SSD drives, so I'm probably going to stick to old fashioned disks for the near future, until prices go down and all the kinks are worked out.
Basically, the double-bandwidth is handled pretty seamlessly because the new cards are using PCI express 2.0 rather than the 1.0/1.1 all current cards are using. And SAS2 offers port aggregation, so you can combine 2 SAS1.0 links across a single SAS2.0 link. So your typical expander link would offer 2400MB/sec rather than the current 1200MB/sec, assuming your expander was SAS2 compliant. Sounds like fun... now if only cards were available now...