Flash SSDs dominate the news at present. If you believe the coverage from multiple Internet tech magazines, flash-based devices are about to take over the storage market. They’re perceived as being faster and more efficient than hard drives—and maybe a bit more expensive. The truth is different, though; flash memory still has only a tiny market share for many reasons. The good old hard drive isn’t dead, and we just found another reason for them to live on for a while: short stroking technology.
HDD Vs. SSD
I want to make very clear that we do not favor hard drives versus flash SSDs or vice versa. Each technology has its pros and cons, and each makes a lot of sense when deployed in a smart way. The advantages of SSDs are almost nonexistent access times and high I/O performance. In addition, flash memory has become extremely cheap for capacities of up to 32 GB. Finally, flash SSDs can be amazingly power efficient. Unfortunately, many flash SSD products on the market just are not there yet.
To understand these products, you need to know about the difference between single-level cell (SLC) and multi-level cell (MLC) flash. MLC allows for quick read operations, but the technology is not suitable for high-speed write operations, especially when they occur randomly. SLC flash is superior, but also more expensive. Some MLC flash SSDs are affordable, but the really juicy SLC flash SSDs are still very pricey.
Efficiency and reliability are additional issues. Performance and power efficiency are highly dependent on the quality of the controller used by a flash SSD product, as does power efficiency. There are some amazing products on the market, but they come at a price.
HDDs Holding Up
Conventional hard drives have become extremely affordable, with terabyte drives approaching—or even dropping below—the $100 mark. High capacities, low cost and ready availability clearly are the main reasons to keep using hard drives. And despite being based on magnetic, mechanic, and electronic components, HDDs are typically reliable and comparatively robust. In fact, enterprise class hard drives have to endure torture testing and demanding validation processes before they can be used for mission-critical applications. In contrast, the long term reliability of flash SSDs is still uncharted territory, and hence, they're avoided by many enterprise customers.
Fighting The Physical Disadvantage
The main disadvantage of conventional hard drives is the time delay that occurs each time the read/write heads are required to move. While this is not an issue for sequential read or write operations—where conventional hard drives are often still faster than most flash SSDs—it becomes a serious performance issue for random read and write operations.
Throughput of more than 150 MB/s for fast 15,000 RPM enterprise hard drives can decrease to only kilobytes per second once the hard drive has to access random information that may be distributed across the entire magnetic medium. In other words: the drive or the application loses a lot of time spent on head repositioning operations. What if this mechanical activity could be minimized? It can! We looked at an approach that is referred to as short stroking and tested a set of Hitachi hard drives that aim to reducing mechanical activity by utilizing only a fraction of the hard drives’ capacities.
You know, clicking on this article redirected me to a "Antivirus 360" popup which then said that my computer was infected. My fat ass - I have NOD32.
You guys might want to check where your ads are coming from - only matter of time until one day someone infect themselves.
i just noticed that also, running adscan and virus scan.
Not sure what you guys are experiencing. Running AVG here and no issues. But I'll report it just to make sure. Thanks for the heads-up.
It's odd that you report short-stroking as a process of acceleration. I usually employ short strokes if I'm trying to delay the satisfaction of my I/O needs.
Sorry, couldn't resist.
Interesting article.
I do wish they had a similar to for the WD's and Seagates just to see what kind of boost the higher density platters will provide and maybe you won't lose as much capacity in the process.
Another thought would be for the tool to also allow you to format the one partition for performance but still allow you to use the remaining capacity as you see fit. If I want to try and keep everything in one section I could still get the benefits but if I need to, I can use the remaining room and know that I will get a performance hit.
HOWTO - take your new hard disk drive. Create a 32 Gb partition, from the first LBA block. Format it. Don't forget to enable NCQ if it isn't enabled by default. Store your test data on said partition. Create another partition with the leftover space, where you'll store, say, backups.
Would you mind repeating your tests without using the Hitachi-specific tools, but a mere partitioning tool? 'far as I know, drives access platter sectors sequentially (platter 0 sector 0, platter 1 sector 0, etc.) thus partitioning correctly should have the same effect... That's certainly what I see with my own drives.
Well the results are logical and make sense. Cant say it a new concept, but it is nice to see it on paper.
I got the same popup. The site it came from was "cleanyourpc-now.com".
It spawns a pretty convincing looking explorer window which appears to scan all your drives. It even makes what looks like a bubble pop up above the tray telling you viruses were found.
It's always been known that using less of a hard disk makes it faster but that is hardly likely to make it perform on an SSD like level. HD's are done for when it comes to high throughput work.
If want to make a HD peform better then instead of emptying it and only using 10% of the capacity which is somewhat impractical use a smart defragger that puts all the frequently used data together at the fast end of the disk. That will give you most of the performance most of the time without the disadvantage of a tiny disk size.
Not sure what you guys are experiencing. Running AVG here and no issues. But I'll report it just to make sure. Thanks for the heads-up.
This didnt show up at all on my vista 64-bit that I just tried, but did show up on an older xp machine I used when I first read this article. Bad news.
Didn't get anything here too, I using vista 32-bit but my friend using xp and got some pop up, and now he running his AVG.
I would like to see this in comparison with a RAID of SSD's. Comparing a RAID of short stroke with a RAID of SSD's, to see how they compare... This is very interesting and intriguing information.
Nice article. Didn't expect this kind of stuff from Tom's Hardware.
im using xp and no popups for me. What browser are using those who get it?
It is expectable that dual-head harddisk is coming - one for the outermost track, one for otherwise.
Or may triple head?
I didn't get the anti-virus ad pop up. Then again I'm running Linux and Firefox 3.0+
No popups on Firefox 3.0.7 / Mac OS X 10.5.6
I find it odd that they recommend the crappy onboard RAID in most motherboards...I suppose server/workstation boards have better host controllers equipped onboard.
I ran into the Antivirus 360 problem two days ago visiting Tom's home page; ran AVG and turned up nothing on my computer. IE7 + Vista 64
Back to topic. I think a large Raid array made up of 2.5" hybrid drives or SSD + 2.5" drives is better than an all SSD array. Most accessed data are on the SSD and less accessed on 2.5"