Help with RAID setup

[Dra]

Hey guys,

I'm starting a new build soon, and I need some help with my raid setup. I want to run a RAID 10 on some 1tb drives for my media/storage, as well as a RAID 0 on a few SSDs as my boot and apps drive.

So I have a few questions....

1. Is it possible to run these arrays on the same controller?

2. If it is possible, should I run them on the same controller, or will there be performance loss, especially when accessing both arrays at the same time?

Finally, how would you guys implement this setup, and with what hardware?

Thanks for your help

 

[white_devil]

1. Yes

2. No problem as long as you don't go with some cheap POS controller.

3. How many drives in the RAID 10?

 

[Dra]

Thanks for the reply. I will probably be using eight drives

 

[axan]

raid 10 on 8 1tb drives is colossal waste of space also with that many drives raid 6 is actually safer and wastes less space

 

[ochadd]

-How many video streams and users are going to be accessing the media storage simultaneously?
-How much storage do you need?
-How many SSDs does a "few" mean?
-How important is the data to you?
-What kind of budget are you dealing with?
-Is this a server only or is it also a desktop?


1. All server type controllers I've used can do multiple RAID sets on one controller. PERC 5 and 6, Adaptec 3805 and 5805, lots of old SCSI controllers.

If you are buying the hardware new you might as well use 2TB drives and use as few spindles as possible to accomplish the task. $300 gets you a RAID certified drive that shouldn't rattle to hell in a few years in a many disk set. $120-130 gets you desktop grade drives and you can roll the dice which is probably fine for a entertainment purposes.

 

[cybertron]

raid 10 on 8 1tb drives is colossal waste of space also with that many drives raid 6 is actually safer and wastes less space

Space is not the only factor to be considered in all situations. If OP is using this configuration for any kind of speed intensive application, then Raid 10 would be a benefit over 5 or 6.

 

[john4200]

Space is not the only factor to be considered in all situations. If OP is using this configuration for any kind of speed intensive application, then Raid 10 would be a benefit over 5 or 6.

RAID 10 is probably better for performance for applications that have a lot of random access.

For sequential access, RAID 5 or RAID 6 will probably be faster, since they can read from 7 or 6 data disks in parallel, while RAID 10 would only be reading from 4 data disks in parallel.

 

[sub.mesa]

Are we talking onboard RAID drivers? RAID is just a spec/theory on how to store the files; the actual RAID implementation or RAID engine will determine how much of the theoretical potential you can exploit.

For example, some RAID1 engines allow reading from the mirrored disk as well, simple engines skip the mirror disks for reads and only write to the mirror disk. Some try to read from both but do this inefficiently by letting the disks seek unnecessarily and losing most the benefit ("split" algorithm). RAID5 and RAID6 are a lot more complex and thus the differences between RAID engines are much bigger. Also, modern engines can read from all disks in a RAID5 or RAID6 (or RAID7 for that matter) - by skipping their parity block and reading the next data block instead.

If we're talking onboard RAID then we're talking simple implementations; i would stick to RAID0+1 for the HDDs. The SSDs are best handled on the onboard SATA controller with the onboard RAID drivers; this will yield lowest latency. But you would lose TRIM at least on Windows by RAID0-ing them; so underprovision your drive by creating a smaller partition than the full capacity, leaving a portion unused. This will help prevent performance degradation over time, and also prolong the lifetime of the SSDs.

Good luck!

 

[dandragonrage]

http://www.sosdan.com/raid_5_atto.png
http://www.sosdan.com/raid_10_atto.png

I expect RAID-6 to perform around RAID-5 or worse. That's with my 4 drive RAID array using an Adaptec 3085 (800MHz IOP333) on Windows 7 (RC for the RAID-10 and release for RAID-5).

I'm either going to go back to RAID-10 or possibly switch to NAS using ZFS and RAID-Z.

 

[Dra]

Thanks to everyone who gave their input!

To clear a few things up, I would like to use a discrete raid card probably from LSI or Areca, at least for the storage array. This setup will go into a workstation I will be building in a week or two. I initially thought about 4x x25-V, but will probably just go with 2x X25-Ms.

Also, what are the benefits and disadvantages of running the RAID 0 SSD array on the ICH10R instead of a discrete controller?

 

[dandragonrage]

Also, what are the benefits and disadvantages of running the RAID 0 SSD array on the ICH10R instead of a discrete controller?

BIOS update for the board could make the array format incompatible, and moving a new motherboard might not support it (especially if you move to a different brand of chipset).