about RAID

[JRD]

I see you put some effort on cooling down your system...  :-X :-X

I also like the idea of having multiple HDs, if by any chance you loose a 1 TB HD, you are totally screwd. One the other hand, losing one 320 GB HD might be not that bad if you w@&k on a safe back up system using your spare HD and also an external one!

[Stryker7]

I see you put some effort on cooling down your system...  :-X :-X

Didnt have much choice. The heatpipe on the M2N SLI would not w@&k correctly in an inverted postition. Sinter powder heatpipes will, but the M2N did not have that advanced HP system. So I added cooling for the MB components. The benifiet of turning the MB upside down, is that with any addon card (video, sound, etc ,,,, ) it NEVER made sense to me that the chips would face down. Heat rises and gets trapped in the card. An old ATI 9800 Pro's temps dropped by almost 20 C just by inverting the card. Wonder why ? One of the most basic laws of physics, Heat rises. Who'd a thunk ?

I also like the idea of having multiple HDs, if by any chance you loose a 1 TB HD, you are totally screwd. One the other hand, losing one 320 GB HD might be not that bad if you w@&k on a safe back up system using your spare HD and also an external one!

I started out with 4 HDDs. 3 for a RAID, that I never got around to setting up, and a spare for backups. The others were added by date and size. As the need arose, I added drives. Because there was a time gap, the bigger drives came later after they became cheaper.

[PZ]

... 3 for a RAID, that I never got around to setting up...

An array is an excellent idea for those that are worried about data integrity.  For w@&k, I purchased a Gateway server some time ago that contained a level 5 RAID, and it saved my bacon.  A drive went bad and all I needed do was to swap in a new one with no data loss and no server down time.  Plus, it is kind of fun to implement server technology on your home PC.  ;D

[JRD]

I might try one of those arrays on my next rig... one for games, one for general purpose, one for my back up, one for my wife's backup plus my two external HDs and a laptop... quite boring to manage but if you don't have a well planned backup plan, you are in for a great loss in no time.  :D

[PZ]

You'll certainly have peace of mind with an array  ;)

[JRD]

I googled RAID... didn't know about it untill now :-[

Does it really improve performance on reading data? Does it worth having at home... I'll be reading and saving mostly small files after all, so the cost/benefit might not be good in the end!

Does your motherboard overheat or is it necessary a better cooling system as Stryker7 pointed previously?

[Art Blade]

I read loads  about RAID because I was considering an array. In the end, it's not necessary for a gaming rig. It's cheaper and simpler to do backups.

[PZ]

I'm not aware of any read/write performance changes that would be significant enough to make an array worthwhile.  In my opinion, an array is mostly useful when you have a server (and you do not want to take it offline even for maintenance) because you can hot-swap drives without shutting down the machine.

[Stryker7]

I'm not aware of any read/write performance changes that would be significant enough to make an array worthwhile.

Performance can be greatly enhanced, with a striped array. Especially if using more than 2 disk. There is no waiting on Seek times, reading and writing to buffers, and other disk internals. While one disk is processing data, the other is transmitting data to the OS. By the time it is finished, it starts it processing of info, while the other disk(s) send their already processes data.

Not recommended for storage, ever. Dont try to store critical data. But for a gaming disk, there can be extra performace.

A mirrored raid, is redundant by its very nature, it writes the same exact data to 2 or more disk at the same time, if any one drive fails. then you have a backup without any further effort.

Then there are combinations, and some are very elaborate. And REAL RAID, hardware RAID is conducted thru an addon card. It is EXPENSIVE. and very fast. As a matter of fact, when using HW RAID, the operating system never even sees multiple drives.  From BOOT up, even the BIOS sees only 1 drive, even if there are a dozen physical drives. It is completely transparent to the OS.

If you see a RAID card, for less than about $250 US. It is probably a software RAID, which can still be beneficial.

  In my opinion, an array is mostly useful when you have a server (and you do not want to take it offline even for maintenance) because you can hot-swap drives without shutting down the machine.

This is the real part of the post I wanted to respond to.

One of the reasons that I did not setup my RAID array, is because it is a software RAID. There are chips on the MB, but there still has to be a driver, and the seperate drives are seen by the OS, it just handles them as one drive. But there were early and REAL problems with an array setup with a SW RAID. And it took a while for compatability between the SW RAID of Windows vs the Linux SW RAID. It was really risky and difficult to read the array from both OSs. By the way, Linux has had SW RAID, even back with regular old IDE drives, and it was a step up in performance.

BUT if you have onboard SW RAID, there are still benefiets.

In my BIOS, I have all of my HDDs setup as RAID, operating in AHCI mode, without  setting up an array. Now the chipsets capabilities do vary, but anything made in the last 3 or 4 years, allows for Hotswapping. I can plug and unplug my drives, internal and external (aka eSata) can and should be disconnected from the OS, and then you can physically unplug them if need be.

One last thing is, that my RAID chips, allow for NCQ mode. Which still allows request from the disks, to be processed even faster, allowing for quite a bit more performace than using IDE legacy mode.

There is a ton more info out there. And even if you dont want to use onboard (SW RAID) to setup a stripped or mirrored array, you can still get quite a bit of performance boost, just by using the AHCI and NCQ capabilities.

[Art Blade]

(just a "FYI" -- RAID stands for Redundant Array of Independent Disks)

That was a nice bit of info, cheers, stryker. :-X

How do you create a "stripped" array?

[PZ]

Indeed - a performance increase would be of great interest  :-X

[Stryker7]

(just a "FYI" -- RAID stands for Redundant Array of Independent Disks)

That was a nice bit of info, cheers, stryker. :-X

How do you create a "stripped" array?

Sorry for the mis-spelling, it is in fact striped (RAID 0)

I will be as brief as possible. There seems to be some confusion. Let me simplify. A real quick synopsis.

A "RAID" is, 2 or more disk, setup to operate as though they are one disk. They are a RAID in that the total of independant disk are treated as one,

The "ARRAY" is the filesystem that is created to span the multiple disk, but act as though it is one disk. The type of ARRAY, whether RAID0 or RAID1, or any combination of those 2 are the filesystem of usable space. And not to add to the confusion, but there is a JBOD RAID, which is very limited in that there are no possible combinations, but is in fact, Just a Bunch Of Disk.

RAID0 and RAID1 are 2 completely different things. Back to the 2 basic array types (more commonly called RAID)

To better understand the ARRAY part of RAID, when you setup or create the array, a cluster size for that array can be chosen, or left at default. For this discussion, let us assume that you have created the array using a cluster size of 256 bit .

RAID0 works this way. When the array is created, the 2 disk are treated as one disk, alternating access between the 2.  **EDIT : the alternating is not in time but in placement. In a RAID it is possible to write to 2, 3, or 10 disk, simultaniously. It is not first one THEN the other. That is where the real performance benifiet is.

This is the difference in how the arrays w@&k. If you copy a 2MB picture file to the array, the segments are written to the array in different ways. These differences ARE the different RAID types.

In a RAID0 (striped), the first 256 bit segment (stripe) is written to the 1st physical disk, the 2nd 256 bit segment (stripe) is written to the 2nd physical disk, the 3rd segment (stripe) is written to the 1st physical disk, the 4th 256 bit segment (stripe) is written to the 2nd physical disk,and so on etc etc etc. until the entire 2MB file is written. You have copied the 2 MB file to the array, but the various segments, are written alternately to the 2 different disk. That is why if you have a disk error or failure in a RAID0, that file is lost, permantly and forever.

RAID1 is a mirrored array, the Redundant part. It takes the same 2MB file, writes the entire file to disk1 AND the entire file to disk2. Not in segments (stripes) like a RAID0 array. When you have a RAID1 array, you in fact have an automatic, invisble to you, backup. A RAID1 failure, means you still have a complete copy of the file on the other disk.

Now RAIDs 0+1, 1+0, 3, 4, 5 , 6, 10, 50 are all different types of arrays, and all have their benifiets and requirements. But they ALL are just different combinations of the RAID0 and RAID1 arrays.

Then there is the poor old JBOD. It provides neither the performance or redundancy of the other sorts of RAID. It is just a bunch of disk.

Hope that was not too long winded, and I apologize for hijacking the thread, but I was trying to clear up any confusion. If any admin or moderator, hint hint ART, wants to move my part of the thread to its own thread, I would not be offended at all.

I hope I explained well enough, with my limited knowledge of RAIDs.

[Art Blade]

Excellent, no worries there. I think it matches the topic in a way as it could be part of a gaming rig spec, only that we now have a nice and easy info about RAID systems. We might still link to that post or at some time I could split it off, but I think I'll just leave it be.

Thanks a lot, stryker :)  :-X

[PZ]

Good info, Stryker - much appreciated.  It's nice to know we have a member knowledgeable in RAID in case one of us takes the plunge so to speak  :-X

[Art Blade]

You see, Stryker, now we even created a new board for this stuff and moved the topic over here ;D

[Art Blade]

I finally decided to split this topic off because RAID is too important to be just part of gaming rigs. :)

[Stryker7]

You see, Stryker, now we even created a new board for this stuff and moved the topic over here ;D

Yeah, I see that.

I made a decision today, when I do my Windows 7 install. I am going to pull my PC apart, clean everything up. Get rid of all the dust-bunnies.

When I put it back together, I am going to re-install Windows XP, Install Win7, re-install Linux (probably Ubuntu but we will see.) Then after I get done with all of that, a couple of days at least, I am going to put my RAID together, and make it a gaming partition.

I think I will do some benchmarks of the drives operating in AHCI mode like I am using them now, then build the RAID with a RAID0 Array. I am looking for pure performance, not looking for data backup, ergo RAID0.

I will find out for sure just how much faster a software RAID is for gaming. In theory it should be quite a bit faster, but I have never set up a RAID for gaming, just a media server and an NFS/ Samba server.

This is all going to take some real moving around of stuff, all of my 149GB drives are pretty full of other stuff right now, but I do have these other drives, and a little time.

I do have a couple of question though.

How many people here have RAID chipsets on thier motherboards ? I ask because it might inspire me if I am acutally going to be helping others out with the info.
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To JRD you said that you got a Gateway server with a RAID5 on it. Is that a HW RAID ( with an addon RAID card), or was that another SW RAID with it built-in on the motherboard ?
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Once I start this process in a couple of days, I am sure I wont be back on for a couple of days with HW torn apart and all the OSs to (re)do. But I will be back.

[JRD]

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To JRD you said that you got a Gateway server with a RAID5 on it. Is that a HW RAID ( with an addon RAID card), or was that another SW RAID with it built-in on the motherboard ?
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I did?  ::)

Sorry, but you are mistaken! A couple months ago my wife switched my PC on and described something like a mini-explosion followed by smoke and smell of something burning  :'(

I am pretty sure my PC was a low end machine with a good GPU for gaming! One single HD and an old ASUS MoBo... no RAID whatsoever! And even if I had a RAID installed, it would be a model BBQ RAID by now!  :(

Anyway, turns out I'll be puting a new PC together by the end of the year (I'm not at home now as I'm working away from my home country untill the end of the year), so each and every tip I can gather regarding specs for a good gaming and general purpose PC (for home use) will be very welcome. Those topics here are a gret source of info. Members are truly aware of each others needs and very keen to help, which I appreciate a lot ;)

I'm an end user, I use computers at w@&k, Windows and more recently Linux, to do my job via specific applications, but always ring the IT department when things get nasty on my end  ??? . It means I'm not deep into computers and how they w@&k, only the basics, and will probably hire a guy to put it together for me when I take the plunge and spend some cash on a new PC.  :-[

[mandru]

I've been keeping a thought on the back burner of upgrading my rig with a super raid set up to gain a big speed boost but the baseline criteria that needs to become available is affordable solid state hard drives still seems to be a ways off.

I have plenty of room in my case to add several drives and even an additional power supply to accommodate them but I feel the solid state drives are too small memory wise and too expensive to want to move on that just yet.

If a dependable 10TB SSHD breaks the $100 price mark I'll be ready to jump on board.  :P

[Stryker7]

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To JRD you said that you got a Gateway server with a RAID5 on it. Is that a HW RAID ( with an addon RAID card), or was that another SW RAID with it built-in on the motherboard ?
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I did?  ::)

Sorry, but you are mistaken! A couple months ago my wife switched my PC on and described something like a mini-explosion followed by smoke and smell of something burning  :'(

My apologies. It was PZ that said he had gotten a Gateway server with RAID 5.

I am pretty sure my PC was a low end machine with a good GPU for gaming! One single HD and an old ASUS MoBo... no RAID whatsoever! And even if I had a RAID installed, it would be a model BBQ RAID by now!  :(

Now that was funny. I chuckled a good one.

Anyway, turns out I'll be puting a new PC together by the end of the year (I'm not at home now as I'm working away from my home country untill the end of the year), so each and every tip I can gather regarding specs for a good gaming and general purpose PC (for home use) will be very welcome. Those topics here are a gret source of info. Members are truly aware of each others needs and very keen to help, which I appreciate a lot ;)

As far as putting together a PC. Can you turn a screw driver ? That is about the only tool you need to put a PC together. That is the honest truth. The main thing is patience and not trying to force parts.

The absolute hardest part, is DECIDING what you want. But I can say this, for about half of what it cost to buy a PC from one of the top of the line PCs (alienware, sun systems) you can build your own. Now you know your capablities, but believe me, it is not that difficult.

I'll let ya'll in on a little secret. People that build their own PCs. and talk about how difficult it is, is just trying to make themselves out to be bigger than they are.

By way of example, my 12 year old nephew has watched me build 3 PCs. He recently built his own. Now I was right there, and only had to point out things about 2 or 3 times, but he really built his own.

Then he started bragging to his friends how difficult it was, (see above)  :-[

I'm an end user, I use computers at w@&k, Windows and more recently Linux, to do my job via specific applications, but always ring the IT department when things get nasty on my end  ??? . It means I'm not deep into computers and how they w@&k, only the basics, and will probably hire a guy to put it together for me when I take the plunge and spend some cash on a new PC.  :-[

If you just dont want to do it yourself for whatever reason, and some people just are not interested,  I respect that, you might check with a local Linux user group.

Linux guys are usually pretty savvy when it comes to computers, and you might find someone willing to help you out. If you are from the UK, check this out http://lug.org.uk/. Linux users groups all around the world are great places, with pretty friendly and helpful folks. And a resource for a plethora of computer information.

Cant speak for the UK group, but at our local group, we do montly installfest where anyone interested in Linux, can bring a PC, or MAC, and get Linux installed for free.

[Stryker7]

I've been keeping a thought on the back burner of upgrading my rig with a super raid set up to gain a big speed boost but the baseline criteria that needs to become available is affordable solid state hard drives still seems to be a ways off.

Cost seems to be where most people have the REAL difficulty, myself included. Me and the wife decided to have kids. 4 Girls  ::)  which translates to always being broke. I just cant afford it right now.

Solid State Drives are, or will be, great. Also still too experimental for my taste. But you dont have to use SSDs for a RAID. Besides that. SSDs in theory are so fast, that the bottle neck would be the HW it was connected to.

But if you are really interested in a super raid set up, it can be done real well with about 7 or 8 hundred dollars US.

I have mentioned True RAID, aka HW RAID. A card, about $300 or $400, 3 or 4 SATA 2 HD for $300 or so. If you are really interested, I could ask around for recommendations from some people I trust. Another option would be to buy a used card, but then you are taking chances that way too.

If you have money to burn, $2000 for a card, and 5 or 6 10,000 RPM drives would make a Super RAID setup.

As I already said earlier, a True HW RAID, doesnt need any drivers to run. From the BIOS the computer and any operating system, sees all the drives connected thru the RAID card, as one drive. And they are blazing fast compared to regular HDDs.

I have plenty of room in my case to add several drives and even an additional power supply to accommodate them but I feel the solid state drives are too small memory wise and too expensive to want to move on that just yet.

If a dependable 10TB SSHD breaks the $100 price mark I'll be ready to jump on board.  :P

Was that meant as "when monkeys fly out of my butt" type of statement ? (see Bruce Almighty) :)

Again, SSDs are not neccesary, and I would not recommend them, as part of a RAID setup. If you are really interested, let me know. I would be willing to help if I can.

[Art Blade]

Stryder, thanks a lot for all your input here, appreciated  :) :-X

One of my PCs, I think actually this one, used to boot with a RAID controller message but I got rid of it somehow (when I bought it, it didn't have a RAID set up). It had vista home premium installed which after a "hello, seen you, done with you" I levelled and instead installed XP pro. Now the problem with installing XP on the machine was that it wouldn't install at first. It couldn't find the HD (1TB). After fiddling with the BIOS, I found a toggle which changed some HD feature and made it accessible for XP to install on it. So I am not sure wheather or not it is SW or HW, but I think it's a HW chip on board.

The more I read about RAID0, the more it interests me and I might have one one day (either upgrade this rig or have it in the next rig).

However, don't think that you're wasting your time going into detail here, we have a lot of people just reading our boards and some of them might even pop up here and submit a post ;)

[PZ]

I sure would be interested in the performance data - I was the one with the Gateway server, and it is a hardware (PCI) RAID.  I'm not using that server any more and could yank the parts out of it for my gaming rig.

[mandru]

I had said:

If a dependable 10TB SSHD breaks the $100 price mark I'll be ready to jump on board.  :P

Th which Stryker7 responded:

Was that meant as "when monkeys fly out of my butt" type of statement ? (see Bruce Almighty) :)

Sorry if my comment seemed flippant but If you look at the developments in this field of technology that have come along and become obsolete since I started following it, I don't see my benchmark as being that far in the future.

How many thousand of dollars were the first RadioShack TRS80 adding all the peripherals required to make it useful?  A common gameboy that can be bought for $99 has the processing power to outstrip a warehouse full of those sad TRS's.

Dell is still selling tens of thousands of Core 2 Duo's as new technology to thousands of customers that don't know any better.  I at least had the sense to try to build a system that would be forward thinking to allow for future upgrades by reading all the reviews I could find (and many cups of tea as well).

I'm patient and suspect that what I said really isn't that far down the road.  8)

[Stryker7]

I had said:

If a dependable 10TB SSHD breaks the $100 price mark I'll be ready to jump on board.  :P

Th which Stryker7 responded:

Was that meant as "when monkeys fly out of my butt" type of statement ? (see Bruce Almighty) :)

Sorry if my comment seemed flippant but If you look at the developments in this field of technology that have come along and become obsolete since I started following it, I don't see my benchmark as being that far in the future.

No, I did not take it that way at all, just thought it was kind of funny, and was making an attempt at humor myself.  :). I thought that your proposal was humorous, and my response was meant to be that way as well. 

If a dependable 10TB SSHD breaks the $100 price mark I'll be ready to jump on board.  :P

I am sorry if I mis-interpreted the smiley face at the end of that comment. And to be perfectly clear, I was not trying to portray your response as flippant, nor was my comment meant to be confrontational at all.

Most SSDs now in the 80 GB range in the $200+ range, 500 GB between $2000 and $10,000. The idea of a 1 TB for under $100. That is just a bit humorous.  ;)

How many thousand of dollars were the first RadioShack TRS80 adding all the peripherals required to make it useful?  A common gameboy that can be bought for $99 has the processing power to outstrip a warehouse full of those sad TRS's.

Dell is still selling tens of thousands of Core 2 Duo's as new technology to thousands of customers that don't know any better.  I at least had the sense to try to build a system that would be forward thinking to allow for future upgrades by reading all the reviews I could find (and many cups of tea as well).

I have (had) an uncle that worked for Texas Instruments as a R&D engineer. In the mid-70s, if my memory serves me well, He brought a hand-held calculator to a family reunion. Its cost was to be more than $1000. I said "was to be" because in fact it was a prototype model, and not even on the market at the time. Now you can purchase a pocket calculator, at the checkout stand of any store now, for $1.99.

So I too understand the advancements in technology and the ability to be forward looking. Even better than SOME people that get credit for it, when they deserve none. I am one of the people that made, and still do, great fun of a comment made by one such person who was supposedly an innovator in his field.

Who said "Who would ever need more than 640K of memory ?

Microsoft's founder Bill Gates.

I'm patient and suspect that what I said really isn't that far down the road.  8)

Not to discourage your patitience and hope, but I dont see a  dependable 10TB SSHD anytime soon.

Personally for you, I apologize for any misunderstanding, but I did not mean any disrespect towards your opinion, or your optimistic outlook.