Performance gain from dual non RAID Hard Drives ?

Hello,
Without RAID, does two hard drives offer any performance advantage over one hard drive (for non-video editing tasks) ?

Thank You.

 

Uhh... no.

Two seperate hard drives perform the same as any single harddrive.
It's just... another hard drive.

 

I read in windows KB that putting page file on separate HD offers better performance. So I was wondering are there ways to setup Windows (other than RAID) to get better performance out of 2 HD ?

 

yes, if you put the pagefile on a separate HD, you will "see" a performance increase. honestly, though, you wouldn't actually see it unless you were checking some abstract benchmarks. additionally, powering a 2nd HD is just another drain on the battery.

if you really need that kind of performance, you should be looking towards a desktop.

 

Battery life is not a big issue with me.
Will Splitting Programs and OS in seprate HD help ?
Please advise on all strategies to get max performance out of two 100Gb HD ? (Raid in h/w is not available)

 

No, it won't really help. You won't see any additional speed by putting the swap space on a seperate hard drive. Well, there will be a bit of a difference, but again, you won't notice it.
You could try doing raid through SW mode. I've never tried that, and I'm not sure how good it is.
If this is in a desktop though, I'd recommend buying a raid card. But since I guess it's in a laptop, the best I could recommend is using a software raid.
And yeah, I have tried using swap area on another disk and I also frequently have one drive as my OS and another for my programs on my desktop. But it doesn't change performance, and it's mainly to keep programs and files seperate from the OS disk (for reformatting and stuff).
The only single app that I know will have an increase in performance is in Photoshop. If you set the scratch disk to another disk, it will be a small increase in performance. But with 7200 rpm drives, and enough ram, I don't think it makes much of a difference.

 

Yes, having two non-raided harddrives can provide a performance boost. It can even out-perform RAID.
It depends on what you use it for.

If you have to read two files, it is much more efficient to read one file from each harddrive, than to read both from the same RAID.
One way of exploiting this is to put your pagefile on the other disk, as mentioned above. Or put your games on one disk, and Windows on the other. Or....

*If* you can make use of this, it will give you better performance (and lower risk of data loss) than running RAID. But it depends on what you use your computer for.

Moreover, for most non-server tasks, RAID isn't more than 3% faster than non-RAID'ed disks.
RAID is not some magic silver bullet. Nor does it automatically increase performance more than anything else you could do. It is a (not entirelyt successful) attempt at adapting two disks for usage patterns requiring only one disk. Most of the time, it doesn't give a performance boost, and occasionally it gives you a few percent. (Unless you're running a big file- or databaseserver, in which case it can provide a noticeable boost).

But if you can actually make use of two disks, that is by far the most efficient solution.

 

Thank you. I have two options:
1. Core2 Duo T7600 with one 7200rpm SATA HD.
2. Core2 Duo T7200 with two non-RAID 7200rpm SATA HDs.
Is 1st a better choice as 333Mhz higher speed in C2D will more than compensate slight (?) performance gain from 2 non-raid HD, for ONLY software development use (VS.NET 2005, SQL SERVER 2005, Java/J2EE, Oracle database 9i, etc) ?

 

Um... wow, thats definently not been my experience nor anyone else who's in both in professional and home based use. I've never once, ever, seen using two drives come anywhere near outperforming RAID drives.
OF course, you ahve to consider that you're using the same model/brand drives in both cases.
Using RAID 0 provides a major performance increase. It's day and night in the performance difference. Using two seperate drives, there is no real performance gain. It is small, but you won't really notice it.
There are a lot of benchmarks that show major differencees in RAID performance. Now, if you're doing simple stuff like using word or firefox, you won't notice a difference. But any heavy apps, yeah...
It'll be day and night.

 

The problem wiht your choice is... do you NEED the space from two drives?
Will the 100GB drive fulfill your needs space wise?

If not then, I would suggest going with option A and an external drive, or going with option B.
I personally like to keep my laptop as light as possible, so I wouldn't add a 2nd drive in there.
But really, compiling is more on the CPU side than HD side. For just doing development, the slightly faster CPU will provide you with a higher compile speed. I've never had a difference in speed compiling on any of my computers.
Even those where I have my compilers and IDE on a seperate hard drive than my OS drive.
Go with option B only if you need the extra HDD space.

 

You can speak for all those people?
Anyway, define professional and home based use please. Doesn't make sense to discuss performance if we don't know which cases we're testing.

And what is "your experience"? Have you actually run two otherwise identical machines (obviously both newly formatted and cleanly installed) side by side, one with RAID and another without? And doing this, have you timed and benchmarked the results? Noted which applications showed how much of an improvement?

And you have tested it how?
Here's a bit of reading you might find interesting:
http://www.storagereview.com/articles/200406/20040625TCQ_5.html
http://faq.storagereview.com/tiki-index.php?page=SingleDriveVsRaid0
http://www.anandtech.com/storage/showdoc.aspx?i=2101

Now you have seen two (or one) drive coming quite close to outperforming RAID drives.

Anyway, how have you yourself tested it? Just installed a RAID setup and gone "ooh, thats fast"? Or have you benchmarked it? In real-world usage? Using identical systems? (It's pretty common to take your old system with a 3-year old WinXP installation, go "ooh, that's slow", then buy two new harddrives, set them up for RAID, reinstall, and then say "ooh, that's faster. Well, duh, of course it is, you're comparing a new clean installation to a 3 year old one.

Care to get technical here? why on earth would that be?
Here's what RAID 0 does:
You take both drives and present one "logical" drive to the application. All read/write requests are sent to the same controller, which then figures out which drive should do what under the hood.
In theory, this is definitely more efficient than a single drive. No doubt about that. (In practice this effect is often outweighed by the fact that coordinating two drives leads to higher effective seek times, and the need to go through an extra controller. And the fact that you have two drives' rotational latency to deal with, instead of just one. Normally, for a I/O request, the drive has to spin, on average, a half rotation. With RAID, each individual drive has to spin half a rotation on average, but the I/O request can only be finished once *both* drives have finished, which means you have to wait for the drive that took the longest time to finish its part of the work. And most of the time, one of the drives will have to spin more than a half rotation, which means longer wait time. But if we ignore all this for a moment, RAID 0 is more efficient than a single drive, no doubt about that)

Now, what if we have to read two files instead of one? With a single drive, it's simple, you have to read one, then the other. With RAID? It's basically the same. Both drives will (probably) have to participate in reading both files.

With two drives, you might be lucky and have one file that needs reading on each drive. That means each drive can read their own file and return, without having to wait for the other drive, or the additional controller, or anything else.

That's why I said that two drives can outperform a RAID setup. Of course, this is only true when we actually have the files we need to read spread across both disks. The nice thing about RAID is that it ensures that no matter what data you read, it's spread across both disks. You lose a bit of efficiency that way, but you save the bother of figuring out which files should go on which disk.

Anyway, let me ask you a question. Why do you think database servers use separate disks for logging and actual database storage?
According to you, RAID would be faster.
The obvious answer is, it isn't faster. It's much faster if they can write to the log *while* other disks are working away on the database. It's also safer, because if one db storage disk goes down, it doesn't affect the log, and vice versa. But the performance aspect is *really* important too. (Database logs easily become a performance bottleneck)

Care to show a few examples?

Yep, that's what I said. File servers and database servers will show a benefit from RAID 0.
Unfortunately, I have to disappoint you. Photoshop and games do not qualify as "heavy apps", and do not typically show much improvement with RAID.

 

Games with long load times will notice significant improvement. This has been proven by hardcore gamers who use RAID 0 striping with two identical hard drives. In fact the high end gamer machines---Alienware, Voodoo---all come with RAID controllers and the option to preconfigure the drives to operate in RAID. The reason for this is that if there was a big map file for a game like say BF2, it would be much faster to load even despite the dual HDD seek times if the map was distributed across the two hard drives. Also consider that it is not "dual seek time" in the sense that it is double the seek time...rather, it is really the seek time of the stripe that takes the longest. If you were to implement RAID 1, this would not even be an issue and you would still enjoy the read speed improvement. Remember that RAID can only be implemented across identical hard drives.

Now consider that nearly all of today's games look for one file at a time in a serial fashion during loading screens, so that it is unlikely that you would ever look for two separate files at the same time on two non-RAID hard drives. Everything else is stored in RAM so you would never access the two separate non-RAID hard drives in play. The exception is of course when you run out of physical memory and have to page, in which case it would again be a serial operation that RAID would perform faster at---remember the HDD is idle during normal game play until the page.

Finally, file servers and database servers should never ever ever be implementing RAID 0. If your data is mission critical---and most files in database/file servers are---then you should go the route of RAID 4 or 5. I happen to work with servers, specifically those used for video encoding/decoding, and I can tell you that without RAID we would never have the bandwidth capacity to transfer or store the video files we work with.

So while your argument for dual HDD's (JBOD perhaps?) in non-RAID configuration does have a certain point, it is almost always the case that RAID will outperform any singular hard drive(s) setup in any given hard drive operation.

 

Thank you. So in my scenario of s/w dev (VS.NET 2005, SQL SERVER 2005, Java/J2EE,..) will 2 HD (w/o RAID) outperform C2D with 333Mhz higher speed if:
1. I separate OS and programs in seprate partitions.
2. Keep page file on seprate partition ? (Paging will become important as VS.NET, SQL server etc will run simultaneously)