I have an SS4000-E and for the last year had used it with only one WD 1.5TB HDD. I need more space, and wanted to use RAID 5 to have reliability, and also keep maximum space, so I bought 3 more WD 1.5TB drives and built a RAID 5 array using all 4 to get a 4.5TB RAID. I am running the latest 1.4-b710 firmware. I configured a "home" share of 1200MB, I will use the "user" directories in the home share to back-up 2 MacOS systems, and a "public" share of 1024MB I plan to put shared music and picture files, etc; and have created a disk backup using the back-up software to use some of the remaining space to backup a Windows 7 machine.
Using only 1 hard drive, I could copy files over at about 9MB/s using 100Mbps LAN, or 11 or so using Gigabit. If I had multiple systems writing simultaneuosly it would go abit slower, but no problem.
Now with RAID5 I can only copy to the NAS at about 2MB/s (regardless of 100Mbps or Gigabit LAN. And if I try to access from multiple computers, my PC will timeout and fail to write. The back-up software I am using on the Windows 7, or MacOS will work (painfully slowly) but copying files fails due to time-out.
If I log into the NAS webpage, and look at system status, it will show CPU utilization as 100% busy, 0% idle, and RAM as only 3656KB free, mostly all used in other words.
I bought this device because of reviews I had read saying it was OK running RAID 5, and ultimately planned always to use it in RAID5 setup, but it appears the CPU / RAM are not able to process RAID 5 ECC generation fast enough for multiple devices to access it.
Is there anything I can do to fix this, or something I have configured incorrectly?