I've been trying out Flexraid on a new WHS 2011 build, and prior to installing Flexraid, I was geting 60-70 MB/s transfer speeds between my drives (mostly Hitachi Coolspin 4 TB drives) all on a single Supermicro AOC-SAS2LP-MV8 controller.
After installing Flexraid (I tried real-time RAID, but Flexraid wouldn't start the array after every reboot, saying it needed to be reconciled) in snapshot mode, and adding some of the drives to the pool, now my transfer rates to the pooled drives dropped to ~25 MB/s.
Since it's not trying to calculate parity in snapshot mode, why would the performance of my writes drop by more than 50%? Are there any setting/tweaks to try to fix this? I posted this on the Flexraid forums, but there's a lot more traffic here on this site. I followed Assassin's Flexraid guide in the setup and configuration, but there's nothing in the guide about troubleshooting performance issues..