Thoughts on RAID Performance (PCI vs Onboard vs PCI-X) 1

[kjv1611]

I currently have PCI RAID cards that seem to perform quite well. Of course, on my current board, I do not have PCI-X connections, so PCI was the only choice for hardware RAID.

Oh, and they are all PCI-32, not PCI-64, as I read somewhere that some PCI slots are 64..

Anyhow, what I am thinking about is whether with a newer board/processor, whether keeping my PCI RAID Card will be the best idea or not.

Basically, will I still have a performance gain by doing a RAID 0 of 2 Raptor 74GB 16MB cache drives over using onboard RAID of the newer motherboard (with a Core 2 Duo processor)? I would think so, given that it is a hardware RAID solution, but I wanted to seek some advice from some guys around here.

Also, I currently have a RAID 3 array of 3 drives on another card (3 WD 500GB drives). I'm thinking about moving that to a slower machine, and just using it as a file server - I've asked questions in another thread about that.

In a way, I'd almost like to just do without the RAID setup altogether, b/c it's more headache than just strait plugging in a hard drive for the system. However, I got a HUGE performance jump when I did RAID 0 this last time. But, I'm sure a big part of that was in using the Raptors vs the 7200 RPM drives I had been using...


--

"If to err is human, then I must be some kind of human!" -Me

 

[kmcferrin]

A 2-drive RAID0 will nearly double your throughput over a single drive. Raptors will definitely be faster than normal 7200 RPM drives.

But the answer to all your questions are, it depends. What sort of throughput are you seeing now on your Raptors? It's possible that they are being held back by your 32-bit PCI bus connection, which is shared with other PCI cards. So moving the RAID0 to the onboard RAID on your motherboard could potentially improve performance even more.

But it all depends on what mainboard your get and what RAID controller you are currently using.

Also, I know that there is a perception that integrated RAID controllers on motherboards somehow aren't real RAID, or that they are "software RAID" versus "hardware RAID," but in most instances this is not the case. Most motherbaords that have RAID capability these days have either a separate "hardware" RAID controller chip or use a mainboard chipset that has integrated RAID functionality. The notion of "software RAID" only applies in two cases really:

1. RAID that is configured by the OS instead of in hardware, like using Disk Management within Windows to configure an array (as opposed to the RAID controller's BIOS).

2. RAID5 (or other parity-based) arrays on controllers that do not have a dedicated XOR engine built in, which requires the CPU to perform XOR calculations.

Everything else really is hardware RAID.

 

[ATLMatt]

Go on-board RAID! I have a decent Core 2 Duo based system, and running 2 7200 rpm SATA2 drives in a RAID 0 config is a big boost in speed. You'll be even faster with the Raptors. The system is primarily a gaming system, and load times are much faster with RAID 0. Boot time is also improved, but since I keep cutting things out of Vista it isn't to big of a deal anyway.

 

[kjv1611]

Well, I'm planning on keeping the RAID one way or another. That's a no brainer for me. I do a fair amount of audio editing, and boy does it make a difference!

I haven't picked out a motherboard yet. The processor is supposedly going to be given to me for free. If that doesn't happen, I'll just keep waiting for now before I make that big a change.

I would LOVE to find an innexpensive board (sub $200) that supports onboard RAID that would meet the criteria that kmcferrin mentioned!

As far as the actual throughput I am having right now, I don't have an idea as to the numbers. But I know it's TONS more than what I had before.

Is there any free downloadable program that anyone here has used that will tell you your hard drive throughput? I'm sure it would have to be some sort of test. I would love to get that software, run it maybe tonight, and be able to post some numbers really quick.

Any suggestions on the software?

--

"If to err is human, then I must be some kind of human!" -Me

 

[kjv1611]

Okay, this one looks like it could be a good choice so far:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813128050

Storage Devices
PATA 1 x ATA100 up to 2 Devices
SATA 3Gb/s 8
SATA RAID 0/1/0+1/5

Wow! That one handles up to 8 SATA 3Gb/s connections!

--

"If to err is human, then I must be some kind of human!" -Me

 

[ArizonaGeek]

Abit AB-9 Pro has 9 SATA slots and has RAID 5 built on board. I got one in October last year and it works great. I have three 400 gig drives in a RAID 5 and two 250s in a RAID 0.

Cheers
Rob

The answer is always "PEBKAC!

 

[kmcferrin]

HDTach is a decent program for doing disk throughput testing. I can't recall if it's shareware or free, but I know that you don't need to register to use it for the basic tests that you would want.

Most mainboards these days come with onboard RAID that will do 0, 1, and 0+1/1+0/10/whatever you want to call it. Not as many have onboard RAID 5, but if you're doing anything write intensive I'd stay away from 5 anyway.

 

[kjv1611]

Well, if I end up doing what I think I want to do, I'll just do a RAID 0 for the main system, with the RAID 3 in a separate box for the file storage. That way, I can just leave the storage setup running most of the day, so my wife can get to all the baby pictures anytime she wants (from network - laptop) as apposed to having to turn on the "main" pc. And if it ends up consuming less power, then I'd be in better shape that way, anyway.

If I can do a RAID 0 with the onboard RAID, and have it perform as well or better than the PCI RAID, then I'm all about doing that!

So, kmcferrin, were you saying earlier that some of the motherboards actually do have a separate processor for handling the RAID configuration? I was always under the impression that any onboard RAID configuration used your main CPU cycles, and that is what caused the performance hit.

I'll take a look at the Abit board mentioned above as well. 9 SATA connections sounds awful nice!

--

"If to err is human, then I must be some kind of human!" -Me

 

[kjv1611]

Oh, and I'll try the mentioned program tonight, if I am able.

--

"If to err is human, then I must be some kind of human!" -Me

 

[kjv1611]

Looking at the Abit board, it does look pretty nice so far. all the SATA connections, it has 1 PCI-X 16 connection (I already know that I will not be doing SLI any time soon, so this works for me)... it has 1 PATA connection as well...

I found a review of it at Anandtech, here:

http://www.anandtech.com/mb/showdoc.aspx?i=2799

And at NewEgg, it's $99 after a mail-in rebate. Even more reason to check it out.

http://www.newegg.com/Product/Product.aspx?Item=N82E16813127004

--

"If to err is human, then I must be some kind of human!" -Me

 

[kmcferrin]

Just about any modern motherboard will use either a separate chip to manage RAID or will have the southbridge chipset with an integrated RAID controller that handles the RAID functionality, but either way it's all done in hardware. The only exception might be if you were trying to do RAID5, which in addition to needing a hardware RAID controller chip it also needs hardwre XOR functionality or else it will use your CPU to calculate parity bits. I believe that the Intel P35 chipset using the ICH9 southbridge has hardware XOR functionality, but even if it didn't you're still fine as long as you're not using RAID 5.

 

[kjv1611]

Well, that sells me on it! I'm going to run the test tonight if possible anyway, just to see. Then compare that to any numbers I can find with the new mobos.

I'll be sure to post my numbers here when I get a chance.

--

"If to err is human, then I must be some kind of human!" -Me

 

[ArizonaGeek]

The one thing I don't like about the Abit board is the placement of the IDE controller. But since I have a round IDE cable and it is fairly long & only one IDE device (SATA DVD burners we JUST coming around when I got the board) it isn't too bad. But I've been pretty happy with it. I paid a lot more than $99 for it so that is a smoking deal. Good luck!

Cheers
Rob

The answer is always "PEBKAC!

 

[kjv1611]

I saw that about the PATA and floppy connectors. But I'm like you - I've got rounded IDE cables, and don't even use a floppy anymore, anyway. I may have to give this consideration. In a way I'd like to go ahead and get the newest tech, but to get the amount of features on this board in that, would likely cost over $200.

--

"If to err is human, then I must be some kind of human!" -Me

 

[kjv1611]

Alright, I did both the quick and the long tests - I guess it's freeware, as it didn't say anything about shareware or anything.

Burst Speed 90.4 MB/s

Random Access Time 10.6ms
CPU Utilization 0%
Average Read 78.3 MB/s

According to the program, on burst speeds, mine looked like it was right at the bottom! So, it must have to do with the PCI card, I guess... here is what the program chart showed:

SCSI ULTRA 320 = 320
SATA 150 = 150
ATA UltraDMA 6 = 133
Mine = 90.4

But, if I remember correctly - I'll have to look again, it seems that what I got was about typical, unless you had a PCI-Express RAID card, because the drives never actually deliver all the way up to the limits of their connections - but again, I may be remembering incorrectly.

Based on that, what are your thoughts/suggestions?

ArizonaGeek,

If you can, please take a test of your system drive/array with the same program.

You can download it here:

http://www.majorgeeks.com/HDTach_d672.html

I'd like to see how yours compares, considering the motherboard, and that yours is using onboard connections. That would be MOST helpful!


--

"If to err is human, then I must be some kind of human!" -Me

 

[kmcferrin]

Something definitely sounds amiss with your scores. I just ran a quick test on my system, it's an X2 5600+ running on an AMD690G board with a RAID1 array using 2x250GB 7200 RPM 16MB cache SATA300 drives (WD2500KS is the model) and I got a burst speed of 140.4 MB/s. Now, that could be because your PCI interface is holding you back, or it could be that SATA300 has functionality that skews the burst speed measurements, or I could just be having trouble getting an accurate read because I'm running Vista. My sequential reads ranged from 37-65 MB/s across the surface of the disk.

There are some comparison options in HDTach, and some of the options that it lets you compare to are RAID0 arrays of 74GB Raptors. On an Intel 82801ER controller you should be seeing something more along the lines of 190+ MB/s read and 110 MB/s average reads.

 

[kjv1611]

Well, then this may just be the reason for me to just use the onboard RAID of a new board, such as the Abit board mentioned in this thread.

I am thinking that I had read those numbers for a PCI based RAID with the Raptors elsewhere, but I can't be certain.

I'm pretty sure that it's the PCI bus. I've got all but one of 5 or 6 PCI slots filled - 2 of them are SATA RAID cards, and I have a sound card, 1 USB card, and maybe another card or two - I forget. I've changed it around quite a bit. Either way, it doesn't matter too much about what exactly there is - - if I'm going to just redo it all anyway.

Another thing I noticed about the Abit board was that it does have 1 eSata port already on the board. That's nice in case I ever decide to use an eSata drive for backup.

Now, I just gotta wait for my relative to get his new processor, and cough up the Core 2 Duo. Lucky me.

--

"If to err is human, then I must be some kind of human!" -Me

 

[Nelviticus]

kjv, I think I have a similar RAID card to yours (purchased in the last few weeks). I also get a burst speed of about 90 but the other major figure - I can't remember what it's called but it's something like 'sustained transfer rate' - is very high.

One advantage of using the PCI card over the motherboard's RAID controller is that you don't need extra drivers for the former since your system sees it as an IDE controller. That's only really an advantage when first installing Windows though.

Regards

Nelviticus

 

[kjv1611]

Nelviticus,

That's a good point. One thing that is nice about these PCI cards is that they are recognized by Windows with no drivers required from a floppy disk.

However, I know that some of the newer boards don't require any F6 loading of SATA drivers - not sure about RAID.

ArizonaGeek,

On the board that you have - did you have to do a F6 to load the RAID drivers with Windows for it to recognize a RAID configuration, or no? That would be some important information, considering my RAID array would be on the system drive.

Anybody,
I looked up Intel's Matrix Storage page to find out what the whole Matrix RAID thing is. I think I did read about it before, but I couldn't remember what it said.

http://www.intel.com/design/chipsets/matrixstorage_sb.htm

One thing that I noticed that was VERY interesting indeed - I think. It said that you can use RAID 0 AND RAID 1 even with just 2 drives. I thought in the past that you had to have more than just 2 drives to have a 0+1 RAID ARRAY.

If that is the case, does anyone know whether that gives basically the same performance benefits as a strait RAID 0?

My main desire for the main system will be in its handling of audio editing. And possibly later some video editing - but for now, I probably won't even have the time to delve into that too much.

I do also enjoy playing some high-end games, though I really don't have the time to do that, anyway - so that's the least of my concerns, really.

--

"If to err is human, then I must be some kind of human!" -Me

 

[kmcferrin]

You probably will need to F6 for most modern hardware, unless you're installing Vista. The reason for F6 is to install drivers that are not included in the media. Come to think of it, I had to install RAID drivers when installing Vista too, but you didn't have to do F6 and you could use a CD for the source.

The alternative to F6 on XP/2000/2003 would be to slipstream the drivers into a copy of the Windows CD.

One other nice thing about eSATA is that you can get an eSATA "NAS" (not really network if it's eSATA, though some have both) and have an external storage array with all of the speed of a direct SATA connection. So you could put your RAID0 array in you PC, then connect an external box for all of the rest of your storage. You might even be able to use both eSATA and Ethernet at the same time, meaning the direct-attached PC gets a fast connection and everyone else can access it over the network at a slower speed.

From Intel's page:

When using two hard drives, matrix RAID allows RAID 0 and RAID 1 functions to be combined, where critical files can be stored on RAID 1, and RAID 0 can be used for non-critical items such as software.

That's a very interesting concept. It sounds like it would create the equivalent of two SATA LUNs with two disks, one of them mirrored and the other striped. If that were the case you would end up with effectively two drives in Windows.