Raid 1.5???

[AgaBoogaBoo]

I am partly confused as to what Raid 1.5 is, it is included onboard with the board HERE.

Is it basically just a mirrored hard drive but it can read at twice the speed? Most things other than saving large files would benefit from this, right? I'm talking about booting up, loading game maps, starting programs, etc. (In comparison to Raid 0 please)

Also, I'm not looking for Raid isn't useful for a desktop user, I'm not really going to change my mind now on Raid. I was thinking Raid 0 earlier and backing it up daily onto a seperate drive larger than the two combined, but with Raid 1.5 I still get speed I like and best of all, I don't have to keep a 3rd hard drive in my computer allowing me to get a 3rd but modded with a window on the top and LEDS inside.

 

[AgaBoogaBoo]

Really, I need an answer. I'm not kidding

 

[OverVolt]

Read the Website...

It says it had the benefits of RAID 1+0 (10) but, only requires two hardrives, instead of four.

I've never really heard anything about it before, it might be some kind of propietary standard, maybe some one else can give a better explanation.

 

[Lord Evermore]

Dear lord that is the most annoying site ever. And zero non-Flash options.

Oh god! http://www.dfi.com.tw/Upload/News/US/arch168.jsp

It's just frigging RAID1 mirroring! All RAID1 mirrors get higher performance by reading both drives at the same time, assuming the controller and drivers are programmed for that. They're pimping a standard configuration as something unique, perhaps because most IDE RAID controllers don't do it? I sort of doubt that they've gotten some special controller chip and drivers that nobody else has.

Heck, downloaded the driver package. It's just a highpoint 37x controller. Even the manuals for it say RAID 1.5 instead of RAID1, so I guess they've decided that by including the reads from both drives at once as we would expect, they've made some special product.

 

[AgaBoogaBoo]

Originally posted by: Lord Evermore
Dear lord that is the most annoying site ever. And zero non-Flash options.

Oh god! http://www.dfi.com.tw/Upload/News/US/arch168.jsp

It's just frigging RAID1 mirroring! All RAID1 mirrors get higher performance by reading both drives at the same time, assuming the controller and drivers are programmed for that. They're pimping a standard configuration as something unique, perhaps because most IDE RAID controllers don't do it? I sort of doubt that they've gotten some special controller chip and drivers that nobody else has.

I think its also because many low end Raid 1 cards don't really support the read speed of 2 hard drives.

 

[sharkeeper]

There is no specification of RAID 1.5.

Some HBA can optimise reads for better performance off RAID1 arrays using specialised read ahead algorithms, elevator seeking, disk surface synchronisation, etc. None of these features are available on a bargain basement IDE adapter for sure.

From a physical standpoint, there is no way to get continuous streaming STR from a mirror that matches that of a stripe!

-DAK-

 

[Pariah]

From a physical standpoint, there is no way to get continuous streaming STR from a mirror that matches that of a stripe!

Depending on the file size and stripe size of each configuration, you can come up with scenarios where the RAID 1 array could in fact read faster than the RAID 0.

 

[Lord Evermore]

Promises TX controllers split reads between the drives (at least current ones do). They're not bargain basement of course, but they're also not SCSI RAID-level controllers. Presumably the 37x highpoint controllers do the same things, but it's odd that DFI is using older controller chips and marketing something that everyone has as something special.

 

[AgaBoogaBoo]

So what kind of performance can I expect then? I'm definately going RAID for the performance, earlier it was Raid 0 and backing up the Raid configuration's drive to another drive nightly. I'd prefer not having to do that, but not at the cost of only getting the speed of one hard drive just so I can have it mirrored. I also don't want to spend $50 for a Raid card and I saw this motherboard with IDE Raid. In a comparison view, is it just the same as Raid 1 with a read speed of close to what two drives read at only advertised as "Raid 1.5?"

 

[AgaBoogaBoo]

Is there a special name for the technology within Raid I am talking about? I know I can go Raid 1+0 but that is out of my wallet's reach not to mention the need for another fan within my case with 4 hard drives. Basically, I can use two hard drives, and I want to get faster speed with mirroring. Right now, this is my only visible option.

 

[sharkeeper]

Depending on the file size and stripe size of each configuration, you can come up with scenarios where the RAID 1 array could in fact read faster than the RAID 0.

When using the LD for its intended purpose, I assure you there is no way on Earth (or any place else for that matter) that will be the case! Remember, it's possible to have nPD x zCH per LD! With RAID1, nPD is ALWAYS TWO! Combining RAID1 arrays into LD's doesn't count (RAID10).

We use RAID0 for one thing. To move large contiguous streams as fast as possible. Each PD (15.3) has ABMAX at OT of ~76 MB/S decaying to ~51 MB/S ABMAX at IT.

-DAK-

 

[Pariah]

Would you like to speak in English so the rest have some idea what you are talking about? Stuffing as many abbreviations as you can into one post does not make you right. It's pretty simple, if you setup a RAID 0 array where the average file size is smaller than the stripe size while you create a RAID 1 array which load balances reads and has a smaller stripe size than the average file size, the RAID 1 array will stream data faster than the RAID 0 array.

 

[sharkeeper]

This rule is correct with a PAIR of drives in RAID1 when unusual circumstances take place vs. a PAIR of drives in RAID0.

Faster data retrieval time may be a better term. Overall, the end user would NEVER be capable of feeling the difference.

The speed difference becomes readily apparent once four or more drives are striped within a single logical drive.

Sorry, I presumed the abbreviations are readily understood by people here.

Settle down and have a cold :beer:

-DAK-

 

[AgaBoogaBoo]

I somehow have understood everything said so far, even though it took a few minutes extra to read, I'm surprised I could get through it.

Anyway, this must mean that if I set it up correctly, my read speeds *can* be somewhat close to what they would be if it were a Raid 0 setup? I'm really just wanting a faster boot time and lower map loading time on games. This Raid 1.5 would do this for me, right?

 

[Lord Evermore]

Yes. What's being advertised as RAID 1.5 is really just RAID1 with all the features that are normal with RAID1, rather than being a slightly crippled version that you might expect with a low-cost controller. You'll get faster reads than a single drive in many cases, certainly no slower, and almost as good as RAID0 sometimes. However writes will be slightly slower, I really don't know why that supposedly happens with a mirror array, I'd expect the controller to be able to handle the processing for duplicating the data to both drives as easily as it handles splitting the data for a striped array.

Incidentally, the onboard controller is exactly the same as an add-in controller card, it's just mounted on the board and wired permanently to the PCI bus traces.

I think you can probably find a better board for a low price, and not one that uses quite so heavy a gimmicky name for RAID. Most boards come with a newer controller too, the 37x has been around a long time.

 

[AgaBoogaBoo]

Originally posted by: Lord Evermore
I think you can probably find a better board for a low price, and not one that uses quite so heavy a gimmicky name for RAID. Most boards come with a newer controller too, the 37x has been around a long time.

Most likely, but I'm not worried about a gimmicky name and this board has everyth ing else I want plus lights to impress my friends with and some nice round cables, don't get me wrong about my intentions about buying this mobo. I'm not buying it for the extra stuff, but because it has EVERYTHING I want in a motherboard and I have to get an 875P motherboard anyway and with this one I get nice lights and cables.

Thanks. :beer:

 

[Lord Evermore]

Oh. You're one of those people.

I still think buying a board with old hardware on it just to get some other non-essential toys is kinda silly.

 

[AgaBoogaBoo]

Originally posted by: Lord Evermore
Oh. You're one of those people.

I still think buying a board with old hardware on it just to get some other non-essential toys is kinda silly.

Well, the rest of the stuff seems new, isn't it?

If the RAID controller is the only old thing on it, I'm not worried.