I was never able to figure this out. I ended up moving the data to the ZFS pool. The idea was this drive was going to be used for frequent I/O to keep me from spinning up the ZFS pool or leaving it running all of the time.



I have no clue what is causing it, odds are it is an issue with the way FreeNAS handles I/O. Since it runs the stock FreeBSD 7.2 Kernel I don't know what changes would have been made that could affect I/O that badly. I've tried FreeBSD on the same box and it has 20-30MB/s transfer but as soon as I switch to FreeNAS the speed drops to 3-5MB/s It has to be a problem with FreeNAS but I haven't been able to find anyone having the same problem till now.



To clearify, what hardware is your FreeNAS box running, mobo, ram, cpu, and such. My guess is there is a common factor in the hardware that may be triggering a timing problem in the kernel causing it to take forever to complete an I/O process. However, this doesn't make sense either because the I/O Wait would not increase from 0. Which indicates that the kernel isn't getting backed up with data requests.



I am at a loss for what would cause that amount of performance degradation.