Solid-state drives are all the rage lately, thanks to their high transfer speeds and ultrafast access times, but most people still use cheap, spacious mechanical hard drives. Unfortunately, mechanical hard drives also constitute one of the most significant performance bottlenecks in modern computer systems. Even when paired with the fastest processors and lots of memory, a slow hard drive will drag down the a system's overall performance and responsiveness, which is why upgrading to an SSD usually yields such significant performance gains.

If upgrading to a solid-state drive isn't the cards for you right no, you can improve the performance of your hard drive through a technique colloquially known as "short stroking." In simple terms, short stroking a drive means partitioning it so as to use its highest-performing sectors. Hard drives perform differently depending on where data is stored on their platters. Knowing where the fastest sections of the drive are and partitioning the drive to take advantage of them are the keys to optimizing it.

Finding the Sweet Spot

Generally, the smaller you make the initial, primary partition on a hard drive, the better that volume will perform. But no one likes to be limited by a tiny volume size, so it's very useful to be able to determine where transfer rates begin to drop off on a hard drive. With that information in hand, you can tune your partition to balance overall performance against volume size.

All you need is a benchmark tool like HD Tune or HD Tach that evaluates performance across an entire drive and graphs the results. We used HD Tune in our tests.

To measure a hard drive's performance, you'll need access to a system that already has a fully functional OS installation on another drive. Connect the drive you want to test to this system as a secondary volume, and then run the benchmark tool. You'll notice that performance starts at a relatively high level and then gradually tapers off. For this article, we tested a 1TB Western Digital Velociraptor drive and initially saw transfer rates in the vicinity of 210 megabytes per second, which gradually slowed to about 116 MBps. Similarly, access times were fastest in the early part of the test and grew slower as the test progressed. This phenomenon occurs because hard drives are fastest when they access data from the outermost tracks on its platters. Given a constant spindle speed (10,000 rpm, in the Velociraptor's case), the drive's read/write heads can simply cover a larger area in a shorter amount of time when positioned over the outer edges of the platter, resulting in better performance.

For optimal system performance, you need to place your OS and all of your most commonly used applications and files in the fastest areas on the drive. Accomplishing this goal involves creating a primary partition of the correct size on the drive and then installing your OS and apps there. You can partition and use the remainder of the drive, too, but you should store only infrequently accessed data there.

With the Velociraptor hard drive we tested, performance began to drop noticeably at about the 200GB mark, as the HD Tune graph above indicates. By the 300GB mark, transfer rates had fallen by about 50 MBps from their initial speed, and they continued to decline from there. 200GB is plenty of space for a primary partition, so that's the size we'd make ours.

Once you've identified the sweet spot on your drive, create a primary partition of the optimal size. You can do this either during the initial setup phase (when installing the OS) or while the drive is connected to a system whose OS is already installed. To create a partition during a fresh installation of Windows, follow the on-screen prompts during the first phase of the setup process until you reach the point of choosing a target drive. Then click Drive Options (advanced), select your drive on the resulting screen, and specify the partition size. To create a partition on a drive connected to a system that already has Windows installed, connect the drive, boot into Windows, click the Start button, type Disk Management in the Search/Run field, and press Enter. The Disk Management utility will open and, if it detects a new blank drive, will usually launch a wizard. If no wizard launches, right-click the entry for the drive in the list at the bottom of the window, and choose the option to create a new volume. Because Windows uses binary measurements in megabytes to specify partition sizes, 1 gigabyte contains 1024 megabytes. Consequently, in specifying our 200GB partition, we had to identify a partition size of 204,800MB (200 × 1024).

Performance Testing

To gauge the performance benefits of short-stroking a hard drive, we ran a couple of popular benchmarks--HD Tune 5.0 and PCMark 7--on our 1TB Velociraptor hard drive, first with a single partition that spanned the entire drive and a second time with a primary partition consisting of the drive's highest-performance, first 200GB of space.

WD Velociraptor 1TB w/ 1TB partition WD Velociraptor 1TB w/ 200GB partition Improvement HD Tune 5.0 (read test) Average transfer rate 164.1 MBps 194.4 MBps 18.46% Minimum transfer rate 116.2 MBps 181.7 MBps 56.37% Maximum transfer rate 207.3 MBps 210.7 MBps 1.64% Burst rate 336.0 MBps 335.2 MBps -0.24% Access time* 7.13 ms 5.43 ms 23.84% PCMark 7 Secondary Storage Benchmark Overall score 2699 2743 1.63% Starting applications 5.9 MBps 6.05 MBps 2.54% Importing pictures 11.74 MBps 12.17 MBps 3.66% Video editing 21.11 MBps 21.36 MBps 1.18% Gaming 7.97 MBps 8.03 MBps 0.75% Windows Media Center 8.09 MBps 8.11 MBps 0.25% Windows Defender 2.71 MBps 2.82 MBps 4.06% Adding music 1.34 MBps 1.34 MBps 0.00%

* In milliseconds; on this measure, lower scores indicate better performance.

Test system: Intel Core i7-2700K, Asus P8Z68-V Pro (Z68 Express), 8GB DDR3-1600, Western Digital Raptor 150GB (OS), Nvidia GeForce GTX 285, Microsoft Windows 7 Ultimate 64-bit

A hard drive's access times and minimum transfer rates benefit most from short stroking, though the average transfer rate will also jump significantly. According to HD Tune, our drive's minimum transfer rate increased from 116.2 MBps to 181.1 MBps, a boost of more than 56 percent. Also, our drive's average access time decreased from 7.13 ms to 5.43 ms, an improvement of about 23.8 percent. And the drive's average transfer rate saw a nice gain of 18.46 percent, from 164.1 MBps on the 1TB partition to 194.4 MBps on the optimized 200GB partition.

PCMark 7's Secondary Storage benchmark--a suite of trace-based tests that measure performance of simulated real-world workloads, rather than raw transfer speeds and access times (as HD Tune does)--tells a somewhat different story. Though the gains reported by PCMark 7 are less dramatic than those identified by HD Tune, system performance improved nearly across the board. The drive's overall score increased by 1.63 percent after short stroking, with the biggest gain coming in the Windows Defender test, which saw an improvement of 4.06 percent.

Ultimately, short-stroking a hard drive won't raise your hard drive's performance to the level of a solid-state drive. Nevertheless, the right partition configuration can yield tangible gains, as our test results show. A fast storage subsystem usually delivers perceptible performance improvements for the end user, so if you're stuck with a hard drive in your system, why not ensure that it's configured for peak performance?