Working with SSDs in Windows 7 and 8
The introduction of the solid state disk (SSD)—which replaces spinning platters and moving heads with speedy memory chips and fancy controllers—has brought big changes to the computing landscape. In data centers, super-fast disk arrays make use of SSDs to deliver access to "big data" faster than ever. On desktop or workstation PCs, SSDs promise (and deliver) faster boot-ups and shutdowns, quicker access to applications, and zippier performance across the board while engaged at work or play. Notebook PCs get all these benefits, plus increased battery life as a consequence of SSDs' low appetites for power.
Of course, you do have to pay for this privilege. Nowadays, with a GB of storage on conventional spinning hard disks costing between five and ten cents, you're lucky to find an SSD where a GB of storage costs a dollar (more expensive drives can be double that cost, or higher). That means you're paying 10 to 40 times as much for SSD storage as for hard disk storage, without getting the same multiplier for performance.
In fact, you're lucky to get a multiplier as high as 7, and more likely to see multipliers in the 2-3 range for large data transfers as shown in Figure 1, which compares the ATTO Disk Benchmark for an 120 GB OCZ-Vertex 2 SSD (left; cost at purchase $200.00) versus a Samsung 1.5 TB SpinPoint HD154UI (right; cost at purchase $90).
Figure 1 ATTO Benchmark comparison SSD (left) vs. HD (right)
Using SSDs on the Windows Desktop
Nevertheless, SSDs have proven effective enough to justify their higher costs in some circumstances. On desktop and notebook PCs, though, they still cost too much to supplant conventional hard disks altogether.
The most typical configuration used nowadays is a single, smaller SSD for the system/boot drive; along with one or more cheaper and more capacious conventional hard disks for data, documents, and seldom-used applications. Hence, the configuration used to drive the disk benchmarks in Figure 1: this system employs a 120 GB SSD with four conventional hard disks, all sized 1 TB or larger.
Here's an important caveat in sizing an SSD for Windows systems. By default, Windows 7 and 8 allocate 1 to 1.5 times the amount of RAM installed for a paging file (pagefile.sys), and 0.75 to 0.9 times that amount for a hibernation snapshot of memory contents (hiberfile.sys). That means you can (and should) kiss at least 1.75 times the amount of RAM on your system goodbye for such storage.
Table 1 shows what this means for expensive SSD disk space as memory size goes up (all numbers in GB).
RAM size |
Pagefile.sys |
Hiberfile.sys |
Total |
04.0 |
04.0 |
03.0 |
07.0 |
08.0 |
08.0 |
06.0 |
14.0 |
12.0 |
12.0 |
09.0 |
21.0 |
16.0 |
16.0 |
12.0 |
28.0 |
24.0 |
24.0 |
18.0 |
42.0 |
32.0 |
32.0 |
24.0 |
56.0 |
Table 1 — Disk Space for Paging and Hibernation Files, by RAM Size
The take-away from this illustration is, of course, that more RAM means more disk space for the special system files that extend or capture its contents.
Yes, these can be reduced in size through various Windows configuration settings, but to do so limits their usefulness (for example, reducing pagefile.sys below 1.0 x RAM size means you can't capture a complete memory dump should your system crash).
With increasing use of virtualization and 64-bit applications, Windows users are finding 8 GB to be a good working size for medium-duty situations, and 16 or more GB for heavier-duty work. This means you must figure on giving up 14, 28, or more GB of SSD space for these files in sizing your system's SSD. And given that you want at least 25% free space on your system drive to cope with transient space consumption at runtime, that means 80 GB may be too small for many users, and even 120-128 GB marginal.
This probably explains the increasing popularity and purchase of SSDs sized at 160 to 256 GB nowadays. On my current production desktop, for example, with 24 GB of RAM, I decided to upsize from the 120 GB OCZ drive used for the Figure 1 benchmark to a 180 GB Intel 520 Series SSD to gain more breathing room on the system drive.
Other Windows Considerations for SSD
If you purchase a system with an SSD installed, Windows 7 and 8 are smart enough to configure themselves properly for SSD use. But if you upgrade an existing system to these operating systems, you should definitely consider a clean re-install of the operating system rather than cloning a conventional hard disk to your SSD as your migration path from the old spinning drive to its solid-state counterpart. That's because Windows 7 and 8 make certain assumptions about how to configure themselves to behave when installed on spinning drives, and don't necessary re-configure themselves to behave differently when moved to a solid-state drive. On the other hand, you can acquire a very nice tool from German disk partition and cloning company Paragon Software Group called Paragon Migrate OS to SSD for $20 (cheaper if you search for widely available discount coupons online).
The key issues involved are illustrated nicely in Figure 2, which shows Intel's SSD Toolbox System Tuner utility (alas, it only works with Intel drives; download link; screen capture from a test system with an Intel X25-M SSD installed).
Figure 2 Intel SSD Toolbox System Tuner zeros in on key Windows features
Basically, Windows 7 and 8 (and Vista, too, for that matter) make use of a number of speed-up technologies to mitigate the huge difference between memory and conventional hard disk access speeds, which vary from tens of nanoseconds for RAM versus milliseconds (or more) for spinning disks.
SuperFetch and Prefetch are utilities that monitor programs and files accessed, and attempt to anticipate what will be accessed next by caching, so that subsequent accesses are more likely to be satisfied from items already in memory rather than reading the disk. ReadyBoost does likewise.
Device Initiated Power Management lets notebooks manage SSD access and use intelligently on systems running on battery power (and irrelevant on the desktop system where I captured this snapshot).
Turning off the defragmenter is crucial for SSDs, not only because they have no spinning heads and thus gain no benefit from making files physically contiguous (it's always just as fast to access any memory address on an SSD, so file fragmentation literally doesn't matter), but also because writing to SSDs involves reading and writing 1―2 MB per transfer even though block level access usually involves 4 KB chunks of data at a time.
Then, too, SSDs support only a limited number of writes (about 1,000) to any given memory location before it becomes unusable, so you will also shorten the usable life of a drive by defragmenting.
Other Tips for Optimizing Windows 7 or 8 for SSD Use
Windows and applications will let you relocate some built-in storage facilities that write to the C: (system/boot) drive by default. By moving some of these things to other drives, you can save on writes to the SSD, but must also recognize that doing so will result in much slower access to the data involved.
That's why I don't recommend relocating the paging or hibernation files, for example, because they are important to runtime performance (pagefile.sys) and to start-up and shut-down delays (hiberfile.sys).
On the other hand, you may want to consider relocating some or all of the following types of default storage settings:
- Downloads: Right-click the Downloads folder in Windows Explorer; then click Properties. Change the value of the Target field on the Shortcut tab to relocate to another drive.
- Outlook PST files: Click Account Setting; then select the Data Files tab. Select any entry in the data pane, click Settings, and change the path information for the Filename: entry there. Other e-mail packages should offer similar controls for you to move their holdings.
- Printer spooler folder: Click Devices and Printers, select a printer; then click "Print server properties" in the top menu bar. Next, click the Advanced tab; then click "Change Advanced Settings." You can enter a new path and folder specification into the "Spool folder:" textbox on this pane. Changing this value helps only if you have a printer attached to the PC in use.
- Seldom-Used Applications: During the set-up dialog for most applications, you have the option to select a path outside the Program Folders or Program Folders (x86) hierarchy, both of which reside on your system drive. Weigh this option carefully, as you'll be trading space elsewhere against the speed that your SSD would otherwise provide. I take this option only for applications I'm sure I won't use very often, or where performance is not a concern.
If you use a visual disk layout tool like WinDirStat—something I make a part of weekly-to-monthly disk grooming tasks—you will quickly identify the big files on your SSD. Anything you find outside the Windows OS folders that you don't really need is a candidate for relocation.
For applications, this may mean uninstalling then reinstalling, but it can be worth the effort for the space savings you'll accrue. It's also a good idea to use a file cleanup tool like Piriform's CCleaner to keep disk clutter to a minimum on your SSD.
Great SSD Resources Online
There are many great resources on using and optimizing SSDs available on the Web. Some of my particular favorites include the following:
- Elpam.Soft makes a program called SSD Tweaker that comes in a free and several for-a-fee professional forms. You may not want to follow all of its recommendations and implement all of its settings, but it's a real eye-opener to work your way through its features and functions to understand how much using an SSD with Windows can impact your system.
- Les Tokar's TheSSDReview website has all kinds of useful and informative SSD reviews and information. His Optimization Guide is worth visiting—and reading from start to finish! Even he doesn't recommend implementing all of the optimizations it documents, but it's nice to know about them.
- SevenForums is a terrific tutorial and information site for all kinds of Windows topics. Check out the SSD Tweaks and Optimizations in the Windows 7 tutorials or use this Tutorial Search to find a raft of coverage on this topic.
- Sean Webster at Overclock.net has put together a dandy "Sean's Windows 7 Install & Optimization Guide for SSDs & HDDs." The comments and questions are every bit as valuable as his tutorial, so take some time to skim the ancillary materials as well as the "main content." He's also created a Windows 8 version.
There are many benefits to using an SSD with Windows, but chief among these is speed. Follow my guidelines, and dig into the various optimization guides I've noted, to make the most of your SSD experience.