bit-tech.net

IDC: SSD performance gap 'small'

IDC: SSD performance gap 'small'

If you were planning on an SSD as a drop-in replacement for a 7,200 RPM disc, don't expect a performance boost.

The war between traditional mechanical drives and solid-state devices isn't over yet, according to test results published by IDC yesterday – but the battle lines have shifted.

The report, quoted by SearchStorage yesterday, suggests that tests showing a high performance differential between SSD devices and traditional mechanical drives might be a trifle misleading – and IDC's own testing bears that out.

The main complaint the firm has with normal testing is that the comparisons are always between the latest and greatest SSD devices and 4,200 RPM mechanical drives. While the comparison makes sense from the consumer point of view – laptops offered with SSDs usually ship with a 4,200 RPM drive if you choose to save your dosh – they don't make much sense in a world where 5,400 RPM mechanical drives are the norm, and top-end laptops are shipped with 7,200 RPM drives.

IDC researcher David Reinsel compared 7,200 RPM drives with SSD drives and, perhaps most importantly, took the performance of the entire system into account when compiling his results. The conclusion of the research is that previous lab tests on isolated devices may have been misleading, and that the performance gap between the two technologies – while definitely present – is nowhere near as dramatic as SSD proponents have been making out.

Reisnel also point out that the difference in the architecture of SSDs and mechanical drives mean that, despite physical compatability, the devices aren't a simple drop-in replacement at the enterprise end of the market. Rather, many enterprise systems will require a complete redesign in order to achieve the best possible performance from solid-state storage devices. Reisnel is quoted as saying that “there will be what's called a 'period of interdependency' with this technology,” and that the solution won't be simply “plug and play.”

The results of the test are only available to subscribers to IDC's white paper service, so actual figures are currently hard to come by. The company is also being secretive about actual testing methodology, with no mention of what software was used to measure performance on the test units. Nevertheless, if true it is perhaps another blow for the SSD market – currently trying to win back support after researchers discovered that the power saving potential of the vast majority of devices currently on the market was a lot lower than anticipated.

Is the research enough to make you think twice about that expensive SSD investment, or do you need hard figures to be shared before you'll decide one way or the other? Share your thoughts over in the forums.

8 Comments

Discuss in the forums Reply
Dr. Strangelove 17th July 2008, 10:47 Quote
If the SSD's could match the performance of the faster (less energy efficient?) mechanical drives would we not be seeing SSD drives for desktops already?
Gareth Halfacree 17th July 2008, 10:59 Quote
Quote:
Originally Posted by Dr. Strangelove
If the SSD's could match the performance of the faster (less energy efficient?) mechanical drives would we not be seeing SSD drives for desktops already?
The 2.5" SATA SSDs work fine in a desktop - but are much more expensive per gigabyte. If you're asking why there aren't any 3.5" SATA SSDs, it's because it's a relatively small market currently (the main advantage for SSDs, shock resistance, doesn't apply to desktop computing) and because there's no need to make a bigger unit that will only fit in a desktop when you can make a smaller unit that fits in both laptops and desktops.
Liquid K9 17th July 2008, 11:05 Quote
SSD's are still as-good-as-theoretical while the price per gigabyte gap is so immense....
Quote:

1TB Seagate 3.5" 'regular' Hard Disk Drive - approx 120eur (0.12c per gigabyte)
128GB 2.5" OCZ Solid State Disk Drive - approx 400eur (3.11eur per gigabyte)

thats a difference of 2.99eur per gigabyte - or a 2,400% premium. still sound like a viable option to you? not me.
iwod 17th July 2008, 12:07 Quote
One reason would be none of the current OS has optimization for SSD.
SSD has a future for much greater speed. Intel has said their SSD is going to be 200+ MB/s ... although it still hasn't appeared yet.
wuyanxu 17th July 2008, 12:14 Quote
Quote:
Originally Posted by iwod
One reason would be none of the current OS has optimization for SSD.
SSD has a future for much greater speed. Intel has said their SSD is going to be 200+ MB/s ... although it still hasn't appeared yet.
Windows is optimised.

putting Vista on Raptor greatly increases Windows smoothness, so putting on a high performance SSD should increase it even more.

the "small gap" is just saying in comparison to high speed HDD, it's not a large improvement. after-all, current high speed HDD (veloci-Raptor) is already very fast
Gareth Halfacree 17th July 2008, 12:19 Quote
Quote:
Originally Posted by wuyanxu
Windows is optimised.
In no sense of the word is Windows 'optimised' for anything, much less SSDs. By default, Windows writes a large quantity of temporary files to the boot volume - along with a pagefile containing data swapped out of RAM. This constant read/write cycle impacts on the SSD due to the limited number of writes available to Flash memory. Basically, running an unmodified OS on an SSD will result in an expensive paperweight in a short length of time.

Now, you can turn the pagefile off and reduce the number of temporary files created (or move both to a mechanical volume), but that's something you have to do. Likewise, you can do the same in Linux and, I assume, MacOS. That doesn't make either of those 'optimised' for SSD use either - unless someone has already done so and released a special version, such as the SSD-optimised Eeebuntu Ubuntu variant designed for the Asus Eee PC.
chicorasia 17th July 2008, 14:16 Quote
All speed and lifecycle issues aside, has anyone ever tried to recover data from a damaged SSD?

If a controller chip burns out, can you still recover your data? Is there such a thing as a block-by-block clone of the SSD? How do software tools such as Data Rescue II cope with SSDs?
desertstalker 18th July 2008, 03:52 Quote
The manufacturers specify 10s of years if you write the entire contents of the SSD each day, (ie if you have a 128GB device and write 128GB of data to it each day it will last 10+ years). The problem of flash wearing out is almost a non issue these days.

The wear levelling algorithms will ensure that individual sectors do not get prematurely destroyed by pagefiles etc.
Log in

You are not logged in, please login with your forum account below. If you don't already have an account please register to start contributing.



Discuss in the forums