Hard Drive Benchmarks - Single vs Multiple Drives

[Mr Bob]

I'm trying to find some benchmarks or information on performance differences between running a single drive compared to two drives.

How much of an increase is seen when transferring large files?

What about I/O times for file access?

Just talking fairly general, I understand it will be different depending on the hard drive, motherboard/controller.

Any info/links/etc are appreciated

 

[MalVeauX]

Heya,

By multiple drives, are you referring to RAID0? In general, you'll see a curve when it comes to scaling performance in RAID0. For two drives, it's nearly double, but not quite, for large file sustained transfers. But each drive you add to RAID decreases its access time, making it even worse for random small file access. RAID0 really is not that great for performance any more. It used to be all we really had. RAID0 is only good at large file transfer rates. You can short stroke an array to make it even faster and reduce access time, but if you do that you might as well just get an SSD and the SSD will still beat it in general use (IOPS, random small file read/writes, etc).

For example, my single SSD performs as well as two WD 640Gb 7200rpm drives in RAID0. But, my IOPS is multiple times higher than the HDD RAID0 array and my access time is near immeasurable whereas the RAID0 array's access time is like 12ms. Even when short stroked down to 128Gb in RAID0, my SSD beats the two drives in RAID0 in IOPS and access time.

If you're trying to get the best performance you can, you should get an SSD. If the price is keeping you away, well, you said multiple drives and the price of two drives is very close to that of an SSD. The only real advantage anymore is the capacity of HDDs.

NewEgg has a shell shocker going right now for a 64Gb SSD for $120 basically. It's a very good deal if you're looking or a good performance drive on a dime. It's not the best/fastest SSD out there, but it is still faster than RAID0 HDD arrays. The IOPS and access time simply smoke HDD's in comparison. Grab one if you've been waiting. It's a ridiculous price. Two of them in RAID0 themselves would be blistering for the cost.

If your sole use is for huge file transfers, stick with HDD in RAID0. You will get very good capacity and transfer rates for the money. I just hope you're not doing it over a network, even gigabit, because you'll find real fast that the gigabit network will limit your ability to move data beyond the network's actual throughput (not its theoretical throughput).

It would be easier if we knew what you were planing on doing, the size of the files, how they're transferred, where they're going, etc (not that you have to give personal details, but I think you get what I'm saying).

Very best,

 

[Mr Bob]

Not talking about RAID, just multiple internal drives.

Having your programs running on one drive, and files/data accessed from another drive or other multiple drives.

 

[Fayd]

Not talking about RAID, just multiple internal drives.

Having your programs running on one drive, and files/data accessed from another drive or other multiple drives.

that kind of thing is really hard to make a benchmark for.

suffice to say that reading and writing to the same drive at the same time reduces the speed of both operations. that's simple logic.

 

[Mr Bob]

suffice to say that reading and writing to the same drive at the same time reduces the speed of both operations. that's simple logic.

- Simple logic, yes, but I asked for benchmarks... wondering how much of a difference will be seen, not if there is a speed increase.

 

[Slugbait]

You'll have to do a lot of searching, there's plenty of info out there, much of it masked in noise.

It's common knowledge to place your Photoshop scratch disk on a different hard drive for a perf boost. And having half of your pagefile on the OS drive, with the other half on a second drive, also lends a perf boost...as long as the second drive is as fast or faster than the OS drive.

Otherwise, what fayd said: that kind of thing is really hard to make a benchmark for.

 

[0roo0roo]

doesn't really matter now.
if you can buy multiple disc drives and need speed you buy ssd. the speed of stuff like the intel ssd is simply ridiculous compared to regular drives. you might only wonder how much faster ssd raid is perhaps.
raids not going to reduce that seek time to ssd level ever

running multiple drives without raid, sure you get some benefit. random access rapes transfer speeds, the less contention for drive resources the better. but well you can do that and a single intel ssd will still blow it all out out the water.

 

[piasabird]

What I would think is that the larger a drive the harder it is to scan it or defrag it. I am surprised they dont have a hybrid SSD/SATA HARD DRIVE.

I could be wrong also. Typically a lot of drives use a single disk. However, using two or more disks may be even faster. It depends how the scanning/defrag software is written. It would be nice if you could scan multiple disks at the same time.

 

[0roo0roo]

there would be no point to it. easier for someone to simply buy one of each. that way they can get the exactly type of each they want/can afford.

the larger the drive the faster it tends to be so it doesn't matter.

 

[elconejito]

I don't have a benchmark, but from personal experience I'll say if you do a copy from one drive to another drive you get the full speed of the slowest disk. So if I'm transferring from a WD 640GB to a WD 1TB I get ~100mb/s (unless either drive is really full).

Copying to/from the same disk I get less than half so on that same WD 640mb/s I get maybe 40mb/s.

These are just ballparks figures I've seen from watching the built-in Vista speedometer during file transfers of large (multi-GB) files.