Boost Vista Performance with ReadyBoost

On the plus side, one of the Vista's most useful new features is a utility called ReadyBoost. This utility lets a user to plug in a compatible Flash drive and turn over some (or even all) of the drive's storage space to the OS. Vista can then use the Flash drive as part of its own cache, in addition to however much RAM is already installed on the computer system.

This is important because the OS or system cache is invariably the biggest consumer of RAM on any Windows system. (If you don't believe this, just look in the Physical Memory pane in Task Manager at any given moment.) As a result, by deploying ReadyBoost, you can measurably boost the performance of Vista systems.

Unfortunately, ReadyBoost does come with a few "gotchas." First and foremost, not just any Flash drive will be suitable for such use. According to Microsoft, to qualify for its "Enhanced for ReadyBoost" product designation, a Flash drive must deliver a certain level of read/write performance. More specifically, says Matt Ayers, a program manager in the Microsoft Windows Client Performance Group, a qualifying Flash drive must support throughput of at least 2.5 MB per second for 4,000 random reads, and at least 1.75 MB/sec. throughput for 512,000 random writes. In other words, many Flash drives--especially older ones—are too slow for ReadyBoost.

Going deeper into Vista's ReadyBoost, I discovered a few other limitations:

• Only USB Flash drives currently work for ReadyBoost use. This means that flash card readers, multimedia or memory cards such as SD, MemoryStick, MMC, and so forth--which also typically work through card readers of one kind or another—won't support ReadyBoost. That's true even if the media is fast enough to meet ReadyBoost read/write speed requirements.
• ReadyBoost cache space tops out at 4 GB, so there's no point in trying to increase ReadyBoost storage beyond that limit. When I tried to do so as an experiment, Vista seemed to delight in resetting the ReadyBoost cache size to some size smaller than 4 GB, with no discernable pattern in its settings.
• ReadyBoost cache may be allocated on only one suitable device at a time. Even though you may have several open USB ports on a PC and numerous ReadyBoost-capable Flash drives, you can use only one at a time.
• When you eject a ReadyBoost-capable Flash drive from a Vista machine, the reserved space for the ReadyBoost cache on the drive is also removed. This means that the next time you plug the drive back into a Vista machine to use it as a cache extension, you'll have to set ReadyBoost up all over again. But if you just yank the drive, it appears as a file named ReadyBoost.sfcache on that device, and the space remains inviolate, even on other Windows OSes. Therefore, to keep using a Flash drive for ReadyBoost, don't use the Explorer Eject function or the Remove Hardware Safely widget that Vista so thoughtfully makes available on the taskbar. Instead, simply remove the Flash drive from its USB port. That way, you'll be able to resume ReadyBoost the next time you plug that drive back in.

Nonetheless, ReadyBoost is pretty cool, as it does markedly improve Vista's performance. I will describe more included improvements later on in this Recipe by comparing benchmarks. But first, let's give ReadyBoost a whirl and see how it can work for you. INGREDIENTS

To try ReadyBoost on a Windows Vista system, you'll need the following components:

• A PC running any version of Windows Vista: Home Basic, Home Premium, Business, Enterprise, or Ultimate.
• An unoccupied USB port on the PC you're using.
• A ReadyBoost-capable USB Flash drive. In the specifications for prospective purchases, you should see terms such as "ReadyBoost compatible" or "Enhanced for ReadyBoost" to tell you if the drive supports ReadyBoost. Fortunately, as you'll see in the Recipe, Vista can test a Flash drive's suitability.

5 STEPS TOWARD PUMPING UP VISTA'S PERFORMANCE WITH READYBOOST

For any ReadyBoost compatible USB Flash drive, using that capability is almost as easy as plugging in the drive, enabling ReadyBoost, and letting ReadyBoost do its thing. What follows are 5 steps to getting started with ReadyBoost. Unless you hit a snag along the way, the whole process should take less than 2 minutes.

• Select a USB Flash drive, and plug it into an unoccupied USB port on your PC. An AutoPlay window should pop up on your screen. In the following screenshot, I've highlighted the "Speed up my system" entry to check ReadyBoost capability for the inserted Flash drive:
• Although you can't necessarily tell from the information shown in the next screenshot, Vista has tested that Flash drive in the background and found it ReadyBoost capable. What you do see is a radio button to enable use of ReadyBoost on the drive, which is turned off by default.
• Normally, ReadyBoost picks a cache value that's about equal to half the space on the Flash drive. In this case, the Corsair Survivor module I used for testing is 8 GB. That meant the happy consequence of ReadyBoost choosing a maximum cache size of 4,090 MB, which is as close to a true 4 GB (or 4,096 MB) as ReadyBoost gets.
• All this interaction occurs in the context of a new ReadyBoost tab that appears in the Properties window for the drive letter associated with the Flash drive in question. Here's a look:
• In the next screenshot, Vista is shown tacitly indicating that the Flash module is ReadyBoost-capable, because Vista makes it possible for you to turn ReadyBoost on.
• Turning ReadyBoost on is as simple as clicking the radio button next to "Use this device." By default, the cache size is the maximum that ReadyBoost supports for Windows. In the following screenshot, I've turned ReadyBoost on. But it's still necessary to click either the OK or Apply button before Vista will create the ReadyBoost.sfcache file on the drive.
• If you want to resize the ReadyBoost cache file, then either move the slider or type a new value into the numeric cache size value box to its right. In some cases, you'll want to increase cache size; but don't go beyond the limit of 4090 MB. In other cases, you'll want to decrease it.
• Microsoft's Ayers indicated to me that the optimal ratio of ReadyBoost cache to RAM falls in a range from 1:1 to 2.5:1. My own testing confirmed that, too. So for a system with 1 GB of RAM, you'll want at least 1 GB in the ReadyBoost cache—and not much more than 2.5 GB to 3.0 GB before diminishing returns start to apply.
• In the following screenshot, I've resized the ReadyBoost buffer to match the default size for another 2 GB ReadyBoost drive I tested.
• What happens if you insert a Flash drive that won't support ReadyBoost? If you open the Properties window for that drive and click on the ReadyBoost tab, you'll see a screen that looks much like this one:
• The key language reads: "This device does not have the required performance characteristics for use in speeding up your system."
• Also note the "Test Again" button at the lower right. You can click this button to force Vista to interact with the Flash drive to see if it meets requirements. Occasionally, after reformatting the Flash drive to destroy all traces of prior cache files on the Corsair Survivor, I had to use this button to make Vista recognize the drive as ReadyBoost capable--even though I knew it already was.

MEASURING READYBOOST'S IMPACT

I didn't perform exhaustive benchmarks on my Windows Vista system, which is a unit with a 2.0 GHz Pentium M 755 plus 1 GB of DDR2-667 RAM. But I did run through the Global Performance benchmarks in the popular PC Wizard 2007 utility (available online at CPUID) to get a sense of ReadyBoost's impact on overall system performance. I chose this tool because it's free, works with Vista, and also works with most processors and motherboards that run Vista.

The Global Performance benchmark includes ratings for processor, cache, memory, video, and hard disk performance. I report those results for the following scenarios which follow, in order to show the impact of ReadyBoost versus no ReadyBoost on a Vista system—as well as to provide some idea about the relative impact of ReadyBoost cache size on system performance.

Here are my findings:

• Windows Vista with 1 GB (950 MB) of ReadyBoost cache: About the maximum you'd get from a 1 GB ReadyBoost-capable Flash drive.
• Windows Vista with 2 GB (1,810 MB) of ReadyBoost cache: What I did get from a 2 GB ReadyBoost-capable Flash drive.
• Windows Vista with 3 GB (3,065 MB) of ReadyBoost cache: Which I picked as a sufficiently close enough value to true 3 GB (3,072MB).
• Windows Vista with 4 GB (4,090MB) of ReadyBoost cache: The most I could get on my 8 GB ReadyBoost-capable Flash drive.

READYBOOST'S SYSTEM PERFORMANCE IMPROVEMENTS

To keep things consistent and to sidestep issues related to Flash drive performance, I used the same Corsair Survivor Flash drive for all ReadyBoost tests. I simply resized its cache for each reported test where ReadyBoost was active. As the following results illustrate, using ReadyBoost does provide some benefits to Vista users.

In the following table, numbers that appear to the right of the performance metrics under the column heads that read None, 1 GB, 2 GB, and so forth, come from PC Wizard's Global Benchmark ratings. "None" indicates ReadyBoost is not enabled, and the other numbers indicate the size of the ReadyBoost cache as the benchmark was repeated. These numbers don't correspond to any specific units of measure, but they do provide relative values when compared in the right-left dimension. So, 1610 for Processor Global Performance is higher for no ReadyBoost than for any of the values for an active ReadyBoost cache.

While the PC Wizard benchmark ratings increase for many values when using ReadyBoost, the biggest boost comes from the first gigabyte. There's actually a fall-off for the next 2 gigs. Then finally, there's an increase for the fourth and final gigabyte of ReadyBoost cache.

Also, processor and memory performance both decline somewhat when using ReadyBoost. But video and hard-disk performance both increase. The wins from the latter outdid the losses from the former. Also, I noticed a modest improvement in overall system performance whenever I turned ReadyBoost on, in doing regular work as well as in these benchmarks.

All that said, the biggest wins occur from either matching ReadyBoost cache to RAM size, or maxing out the ReadyBoost cache.

ADDITIONAL RESOURCES

With a little careful shopping, you can find a ReadyBoost device for roughly $15 to $30 per gigabyte of capacity.

You'll find Grant Gibson's ReadyBoost Compatibility List of considerable interest. It identifies most Flash drives that meet ReadyBoost criteria.

Likewise XBitLabs' 4 GB USB Drive round-up may be of interest if you wish to save money or maximize performance.

This interview with Matt Ayers, conducted by Microsoft tools strategist Tom Archer, is worth a quick read.

ED TITTEL is a writer and trainer in Austin, Texas, who specializes in Windows topics and tools, especially PC hardware, networking, and security.