Newb guid to setting up RAID (prolly RAID0)?

[sdsean]

My motherboard has a decent raid controller and I was thinking of setting up
to RAID0 arrays in my box, one for the OS and one for storage.

While i'm pretty technically proficient, I have never set up a raid array in a pc before and was wondering if anyone has any pointers or knows somewhere good on the web. . .

[Oats]

Originally Posted by sdsean

My motherboard has a decent raid controller and I was thinking of setting up
to RAID0 arrays in my box, one for the OS and one for storage.

While i'm pretty technically proficient, I have never set up a raid array in a pc before and was wondering if anyone has any pointers or knows somewhere good on the web. . .

Don't do RAID0, it is pointless for a Sage setup and just makes it more complicated and more likely to fail. If one drive in an array fails you lose the array. The risk gives you extra speed, but in the case of SageTV you don't need the speed so it is extra risk for nothing.

RAID1 is a good option if you need 100% uptime. If a drive fails the PC will still run off the other drive while you get a replacement.

I think the best option if you can stand a little downtime in the event of a drive failure is to have a proper backup procedure in place and not use RAID. If your drive fails you replace it and restore the backup.

[sdsean]

Well I use the PC for other stuff as well (e.g. games, surfing the web). Its both a server and a client.

The machine is stout enough that I can play some game (say Arkham Ayslum), and have sageTV service doing recording and be streaming to the bedroom, (which is beautiful i must say).

Currently SageTV only records to one drive (1TB WD Green), that's formatted with 64KB allocation as they like.

The OS drive where SageTV is installed is not used for recording at all. Just OS tasks and programs
and its a WD 300GB Raptor, so while it is fast. its definitely not solid state or anything.

I was thinking RAID 0 just for the OS, to both give more space and b/c I don't think I can pony up for proper SSD just yet. ( A solid MLC with at least 120GB is still in the $350 + range). I could have a pair of raptors in raid for the same cost.

I also have another 1TB WD Caviar black in the machine that hold all my archived media (10s of thousands of music files, etc). Again here I was thinking another RAID 0 array just to speed up sage start time, scrolling around etc.

My backups are just other external hardrives that don't get used a lot. . .given that I have so much media that's really my only option. . .

I'm not really concerned about 100% uptime. . . I have that pretty much now.
I'm also not really concerned about SageTV speed in terms of recording, since that's not really a bottle neck. More over, just wanting to increase overall system throughput. . . and SSD just seem to pricey right now. . . hence why I thought RAID0 would work. . .

(I don't know that much about RAID other than 0 and 1 though, so please elighten me if i'm missing something).

[stanger89]

Originally Posted by sdsean

I was thinking RAID 0 just for the OS, to both give more space and b/c I don't think I can pony up for proper SSD just yet. ( A solid MLC with at least 120GB is still in the $350 + range). I could have a pair of raptors in raid for the same cost.

RAID-0 is not going to help much for your OS, that's where you need random access performance and RAID-0 won't help much with that.

And I think you're overestimating the cost and/or size of an SSD. I just bought a 40GB Intel X25-V for ~$110. It's not got quite the raw sequential throughput of an X25-M, but it's almost the equal for random access. And as for size, IMO and in my experience 40GB is plenty of the OS/programs. Even with a larger drive (like the 160GB X25-M in my desktop) I only partitioned 40GB or less for the OS.

[sdsean]

Yeah I was thinking that as well (in terms of size need / cost). . .but then again there is the games issue. . .

PC games are usually quite big, and these days I'm not even sure if they let you install them to any other drive besides the os one. I can't remember off hand if Arkham for example even gave me the option. Granted I can uninstall them when i'm done, but still. . .you're talking 4GB or so a pop for some if not more. . .

For a long time I got away with 74GB Raptor drives, and I suppose I could probably make due with a 64GB SSD drive. But I'll have to check my os drive when I get home. . . something makes me think that i'm using more than that. . .

[sdsean]

I guess I should also do more reading on RAID, (part of the point of the original post). . .

So I know RAID 1 is out, RAID 0 you're saying won't be that much help. . . SSD is the only/best option?
(From what I gather other RAID levels just use more disk and combine features of either RAID 0/1).

[will]

Originally Posted by Oats

I think the best option if you can stand a little downtime in the event of a drive failure is to have a proper backup procedure in place and not use RAID. If your drive fails you replace it and restore the backup.

I disagree 100%, a RAID array is an excellent option.

For drives for SageTV I recommend either a RAID 5 or 6 (if you have more than 6 or 8 drives). Make sure you setup your RAID array with 64k stripes and then format the drive with 64K sectors. This isn't just for SageTV, it has been shown that 64k is the sweet spot for RAID 5/6/10 arrays.

RAID 0 will give you a significant performance boost. You will just about get double the read/write speed. A general rule of thumb with RAID 0 is the performance gain is multiplied by how many drives you have in the array. So if have one Raptor drive that reads at 100MB/sec then in a RAID 0 with two Raptors it should read around 200MB/sec. The RAID 0 will help increase your system performance and OS load time.

One word of caution: when using a motherboard to control the RAID array you will probably not be able to ever move the storage array to a different motherboard/system. I use a hardware based RAID controller and if I ever re-build my server I can take the controller with me to the new motherboard and the arrays will be recognized. Also, motherboard controllers aren't as efficient as hardware based controllers. The motherboard uses the CPU for calculations whereas a hardware controller does everything itself.

A RAID array never replaces regular backups, however, I have over 6TB of usable space in two RAID 5 arrays. It would cost thousands upon thousands of dollars to do full tape backups of the data. I backup my non-replaceable files in multiple ways but for video storage and recording drives a RAID array is great. If a drive fails SageTV will still work while I get a replacement drive and rebuild the array.

[stanger89]

Originally Posted by will

I disagree 100%, a RAID array is an excellent option.

The question is what for? Not for a single-user OS drive.

RAID 0 will give you a significant performance boost.

Doing what though?

You will just about get double the read/write speed. A general rule of thumb with RAID 0 is the performance gain is multiplied by how many drives you have in the array. So if have one Raptor drive that reads at 100MB/sec then in a RAID 0 with two Raptors it should read around 200MB/sec. The RAID 0 will help increase your system performance and OS load time.

Yes sequential performance roughly doubles, but access time isn't improved at all and that means that as accesses become more random, the performance gains drop to about nil. Problem is, while a Velociraptor can do about 120MB/sec sequential, their performance plummets dramatically with random accesses (what most PC use is), random access transfer rates are ~1-2MB/sec:
http://www.anandtech.com/show/2865/6

A single SSD will hold it's own against even 2, or 3 Raptors in RAID-0 for sequential reads, but will utterly slaughter raptors (by a factor of 20-30x) in random access.

Here's an interesting video:
http://www.youtube.com/watch?v=93B12ae6jaA

Here's Storagereview's take:
http://www.storagereview.com/western...sd_alternative

I'm not saying RAID is bad, quite the contrary, it can be very valuable. But if your goal is performance for your OS and day-to-day tasks, an application where raw capacity is not very important, SSDs are by far the way to go.

[will]

I do agree that most SSDs can beat pretty much any standard mechanical hard drive based RAID array. I would much rather have an X25-E 60GB for my OS drive w/trim support.

Where RAID arrays truly shine is storage. For example, I currently have three 2TB hard drives in a RAID 5. This gives me one drive (formatted as a GPT partition) with 4TB. I use this drive to store my DVD and Blu-ray collection. When I eventually need more space I will be able to dynamically expand the RAID 5 array to include four 2TB hard drives and then expand the GPT partition to 6TB.

I wouldn't recommend a RAID 0 over a decent SSD drive. However, some people prefer having a larger drive for their OS and no one can deny the fact that ALL SSD drives (MLC or SLC) have diminishing performance returns over time (even with trim support). As long as you purchase a quality mechanical hard drive (such as a enterprise grade 1,000,000 million hour operating drive) it will preform the same on day 1 as it does on day 3,000.

[stanger89]

Originally Posted by will

...no one can deny the fact that ALL SSD drives (MLC or SLC) have diminishing performance returns over time (even with trim support).

I don't know, the benchmarks I've seen for the good SSDs indicate IMO negligible performance drop, but even with any drop it's nowhere close to falling to the level of a mechanical drive.

[sdsean]

Good stuff, this was the kind of info I was after. . .

And in fact I was right. . . SSD is still too cost prohibitive right now simply b/c of the storage need.

I checked tonite, and I'm using 59GB on my OS drive. Granted 30GB or so is Game installations (Dragon Age is freaking 15GB on its own!!!)

I'd like to be able to install even more without having to constantly un-install re-install, etc. But I'd also like better performance. . .so while I'd love to use SSDs, I can't really even begin to use them yet b/c the cost per gig is too high. . .

(quick question aside even though I'm not going to do this, I assume you can use SSD's in a RAID array right?).

So from what it sounds like. . . the perf boost will be there, but it won't be huge all the time, and it really just depends on what you are doing (i assume defraggin also helps hugely here). And for the OS side, it sounds like you'd want to use RAID1/RAID 5 simply b/c of error checking and what not. . does that still give a perf boost (however minimal. . . )?

The mobo I have is an EVGA SLI Classified, which "supports RAID0, RAID1, RAID5. . ."
From what I can gather it uses an Intel chip IHC10R.
I also just read somewhere that the OS volume if in RAID configuration can only be 2TB anyway (I know I say ONLY lol). Is that true, if so all this may be moot. . . don't really wanna go through the hassle for that. .

[sdsean]

BTW just looking at hdd benchmarks, the wd re4 2TB and the samsung spint point f3 1TB seem to be the front runners. . .

while wd is expesnsive (as always) they seem to hold their own in just about every category and are actually rated better than my 300gb velociraptor

so too is the samsung although I have never owned a samsung drive before, which kinda makes me nervous (don't know why). And they are cheap!! only 1TB but hey for $90, and according to tom's hardware they are also quieter. . . interesting

[Oats]

Originally Posted by sdsean

So from what it sounds like. . . the perf boost will be there, but it won't be huge all the time, and it really just depends on what you are doing (i assume defraggin also helps hugely here). And for the OS side, it sounds like you'd want to use RAID1/RAID 5 simply b/c of error checking and what not. . does that still give a perf boost (however minimal. . . )?

The mobo I have is an EVGA SLI Classified, which "supports RAID0, RAID1, RAID5. . ."
From what I can gather it uses an Intel chip IHC10R.
I also just read somewhere that the OS volume if in RAID configuration can only be 2TB anyway (I know I say ONLY lol). Is that true, if so all this may be moot. . . don't really wanna go through the hassle for that. .

In normal PC use RAID0 will give you very little real world benefit. In benchmarks it looks great though. The only time you would see a benefit is in game loading, and it will be pretty small. You have to decide if it is worth doubling the failure rate of your C drive or not.

You said you aren't worried about uptime, so that rules out other RAID levels. RAID 1 and higher are so your PC and data stay online when a drive fails. YOU STILL NEED A PROPER BACKUP. Without raid, when a drive fails your PC and data are not available until you replace the drive and restore the backup.

RAID1 gives you no performance increase/decrease. RAID5 on your motherboard will give you increased sequential read speed (similar to RAID0) but severely decreased sequential write speed.

For a partition over 2TB you need to use GPT. GPT does not work with an OS but it is fine for storage. I don't know why anybody would want a 2TB+ OS partition to begin with.

Originally Posted by sdsean

BTW just looking at hdd benchmarks, the wd re4 2TB and the samsung spint point f3 1TB seem to be the front runners. . .

while wd is expesnsive (as always) they seem to hold their own in just about every category and are actually rated better than my 300gb velociraptor

so too is the samsung although I have never owned a samsung drive before, which kinda makes me nervous (don't know why). And they are cheap!! only 1TB but hey for $90, and according to tom's hardware they are also quieter. . . interesting

Stick with the vraptor for your OS. Yes the other drives may have higher sequential speeds but again that is not what you use. The vraptor has better access times and will be snappier feeling.

If you are looking for storage drives then the speed doesn't really matter as they are all pretty close unless you get Green/Low Power 5400RPM drives. I just get whatever is cheapest per GB.

[will]

Originally Posted by sdsean

I also just read somewhere that the OS volume if in RAID configuration can only be 2TB anyway (I know I say ONLY lol). Is that true, if so all this may be moot. . . don't really wanna go through the hassle for that. .

Windows 7, Vista, and I believe XP Pro 64bit can be loaded onto larger than 2TB drives. You must set the partition type to GPT. The default partition type is MBR which does have a 2TB limit.

I do not recommend using a huge drive for your boot OS. You are much better off keeping the large storage as a separate drive. Also, you have a great motherboard, I use the same for my primary computer. But if you setup a RAID array with the motherboard as the controller then you can NEVER move the array to a different system/motherboard combo. So if you build a 6TB array then you are locked to that motherboard.

I use a hardware RAID controller, one of the reasons is that it allows me to move the array with the controller.

[Fuzzy]

Also, software raid is an option. Though MS has removed RAID5 from win7, and it is only available on server 2k8. The advantages of MS's dynamic disks (software raid) is the ability to mix/match drives, as well as raiding drives across separate controllers. performance is lower, as it's all software, but it is also FAR more portable (can be recovered no matter WHAT the failure (assuming only a single failure). Lose a drive, replace it (not necessarily with an identical one, just one that is same or larger size). Lose a controller, simply buy antoher and connect the drives to it. windows will detect, repair as necessary, and you're back.

The only thing I relly miss about moving to win7 home from winxp, is with XP, I was able to tweak it into working with software RAID5. with win7, that's not an option. (or at least, noone has figured out how to 'trick' it yet).

[pgman]

My DVR storage is a RAID 0 array running on a dedicated PCIe hardware controller by Silicon Image (I don't know what model off the top of my head). I don't know that I see any true performance increase, but the drives I'm using are inexpensive 320GB, which yields me 600+ GB of TV show storage for way less money than I'd have paid for even a 500GB single drive (at that time) - I had the drives laying around and the array controller was only $40.

I don't care that much about reliability - this is just my "scratch" drive that never stores more than about two weeks' worth of shows. Anything important - shows I want to archive - I backup to an external drive. So, my point is that I did the RAID 0 to gain more storage capacity - the extra speed - if any - is just a bonus for me. For what its worth, SageTV DOES seem more responsive with the RAID array than it did before. That may be soley due to the fact that I switched to Windows 7 (from Vista) when I installed the RAID array.

[Oats]

Originally Posted by pgman

My DVR storage is a RAID 0 array running on a dedicated PCIe hardware controller by Silicon Image (I don't know what model off the top of my head). I don't know that I see any true performance increase, but the drives I'm using are inexpensive 320GB, which yields me 600+ GB of TV show storage for way less money than I'd have paid for even a 500GB single drive (at that time) - I had the drives laying around and the array controller was only $40.

I don't care that much about reliability - this is just my "scratch" drive that never stores more than about two weeks' worth of shows. Anything important - shows I want to archive - I backup to an external drive. So, my point is that I did the RAID 0 to gain more storage capacity - the extra speed - if any - is just a bonus for me. For what its worth, SageTV DOES seem more responsive with the RAID array than it did before. That may be soley due to the fact that I switched to Windows 7 (from Vista) when I installed the RAID array.

Your raid card is not a hardware raid card, it still uses the CPU to do raid calculations just like motherboard raid solutions. However, raid0 and raid1 use very little CPU power. A hardware raid card has it's own processor, which is really only necessary for higher raid levels, like 5 or 6.

A better solution in your case would be to use drive spanning. It is built into Windows and allows multiple drives to appear as one partition. If a drive dies when using disk spanning you only lose what was on that drive, not both drives like raid0.

[will]

Originally Posted by Oats

Your raid card is not a hardware raid card, it still uses the CPU to do raid calculations just like motherboard raid solutions. However, raid0 and raid1 use very little CPU power. A hardware raid card has it's own processor, which is really only necessary for higher raid levels, like 5 or 6.

A better solution in your case would be to use drive spanning. It is built into Windows and allows multiple drives to appear as one partition. If a drive dies when using disk spanning you only lose what was on that drive, not both drives like raid0.

Oats is right, the performance hit with your Core i7 processor and motherboard will be negligible, specially with a RAID 0 or 1.

HOWEVER, software RAIDS are notorious for having issues with recovery and rebuilding. I highly recommend that you invest in real RAID controller. You can start off with a RAID 1 and then slowly build it out to a RAID 5, 6, or 10 as your needs change without formatting or losing data (if you get a card that supports RAID expansion).

A good RAID controller is not cheap, mine is the most expensive single component in my server. But I look at it as the most important thing on my server is the data and I don't want the possibility of one drive failing to cause me to lose everything. Also, when a hard drive does fail I don't want to have to spend 12 hours trying to get a software RAID recovery to work. I purchased the high-end controller so I can remove that aspect of stress from my life.

[pgman]

Your raid card is not a hardware raid card...

Well, it IS a dedicated piece of hardware that plugs into the motherboard, as opposed to the on-board controller - that's what I meant.

I've never used drive spanning - don't even know how to set it up. The bigger issue for me was available SATA ports. My motherboard only has four, and I already have a system drive, a music drive and a Bluray drive installed. To do any kind of DVR array, I needed the external "hardware" controller. Can MS drive spanning make use of the Silicon Image controller? If it can, AND my system performance would be better (or at least the data would be more secure), I'd be inclined to try it.

[will]

Originally Posted by pgman

I've never used drive spanning - don't even know how to set it up. The bigger issue for me was available SATA ports...Can MS drive spanning make use of the Silicon Image controller? If it can, AND my system performance would be better (or at least the data would be more secure), I'd be inclined to try it.

I have never used drive spanning before either but it sounds like you would be well severed with using Windows Home Server. WHS allows you to combine any drive (USB, internal, external, etc) into one drive that has RAID type protection.

I have never used it but I know a lot of SageTV users do because it is very easy to setup. But you won't get amazing performance and WHS has had issues in the past, such as the drive becoming corrupted and unusable (I think MS fixed this).

You could also add more internal SATA ports to your system via an PCI-X card.

If you get a RAID card make sure it is a hardware RAID controller with RAM and a processor. You can buy physical RAID controllers that still use the systems resources for the array (these cards usually cost $30 or $40) and are no better than using your motherboard's RAID controller.