Posted July 30, 201113 yr Hi I searched the forum and the wiki but i didn't find anything on this. Is it possible to make a hardware raid 0 for the parity drive? So i take a PCIe raid 0 controller and connect 2x 1TB HDD to it. Configure them in the controller BIOS as raid 0 and select the created drive as parity drive in the web interface of unraid. Then rebuild parity on it. This should speed up parity checks and the write speed of the system. I would like to do the same for the cache drive. But therefore i use 2x 250GB I think that should give a huge boost. I knew that raid 0 doubles the risk of failure but since one disc goes bad it's like i only got a normal disk in the array, i have to replace one drive and then recreate it. So it also could not compromise the system. Is there something that i miss in my consideration? Any point why the created hardware raid 0 discs shouldn't show up in unraid or couldn't be used anyhow? Also a 3TB raid 0 drive (with 2x 1,5TB) wouldn't be functional in Unraid 4.7? would it do in current Beta 5 ?
July 30, 201113 yr I've done RAID0 Parity using 3 methods. 1. Silcon Image Steelvine Processor (Hardware, looks like one SATA drive, cost, within 50-$150) Pros Cheap, Easy, Cost Effective, Double Capacity of Parity drive. Can be external. Can use SAFE 50/33 mode so part of array can be used for Cache drive. Speed Increase. Minimal 1-3MB/s Con Does not spin down, cannot access SMART on any of the drives. 2. PCI-X 3WARE 9750 Pros Cheap, Easy, Cost Effective, Double Capacity of Parity drive. Writes can be cached, Reads are Cached. Speed Increase. Not measured. Should be 1-10MB/s Not tested, but should be able to access SMART stats of any drive in the array, just not from front panel of unRAID. Con Does not spin down from unRAID. unRAID sees it as an odd drive name. 3. Areca ARC-1200 2 port SATA RAID Controller Pros Cheap, Easy, Cost Effective, Double Capacity of Parity drive. Writes can be cached, Reads are Cached. Can do hybrid drive or SAFExx/xx modes splitting capcacity into multiple virtual drives. Speed Increase. Mine showed about 3MB/s SMART monitored at hardware level. Alarm for failed drive. Drives configurable for auto spin down MAX 60 minutes. Con Does not spin down from unRAID. But configurable from controller BIOS. unRAID sees it as an odd drive name. In my configuration I use 2 Seagate 1.5TB 7200RPM drives in RAID0/RAID1 SAFE Mode. 2TB RAID0 Parity 350GB RAID1 Cache I see an improvement (Although small) It matters more when you are doing multiple writes to multiple areas in the array and/or when you are creating or checking parity. I get from 25-50MB/s burst writing on an array drive. I've not measured the cache. I never use the cache as it s designed. I use it as an APP drive and I write directly to the disk# shares. If you monitor eBay you can score the 2Port Areca for $99 or so. I'm very happy with the Areca ARC-1200 as my parity raid controller. However for most people the expenditure will not bring as much as they may expect. It expands and improves my parity performance. but also protects my app drive with RAID1 at the same time. That's of big importance to me. I've yet to acquire 2 7200RPM 3TB drives and try this out. The Seagate 1.5tb drives have been performing so well there has not been a need to upgrade them. I may just wait for the 4TB drives to come out before I venture that way. Related links http://lime-technology.com/forum/index.php?topic=7150.msg69511#msg69511 http://lime-technology.com/forum/index.php?topic=13790.msg130836#msg130836 http://lime-technology.com/forum/index.php?topic=2113.0 Scan for ARC-1200 you will see me and bjp999 mention it a few times.
Archived
This topic is now archived and is closed to further replies.