Optimize disk and memory performance


Disk and memory are arguably the resources that can make the most positive impact on improving client computer performance. Use the following guidelines to help to optimize disk and memory performance in your Windows computer.

  • Select a 64-bit version of Windows. Using a 64-bit version enables your computer to use more memory than the 4 GB limitation imposed by 32-bit operating systems. If your computer has more than 4 GB of memory, or if you can add additional memory beyond 4 GB, then select a 64-bit version of Windows.

  • Avoid shared memory video. Some video adapters use shared system memory. This means that the video adapter uses memory for display purposes that would otherwise be available for servicing applications. Some computers come equipped with video adapters that use dedicated onboard memory for display purposes, ensuring that more memory is available for applications.

  • Optimize paging. For most single disk drive computers that run Windows, leaving the paging file settings at the default values is adequate. However, you might gain a small performance benefit by following these guidelines:

    • Create the paging file on a different physical disk than the operating system disk. Paging is a disk-intensive task. If you distribute the disk load across all of your computer’s available disks, you minimize the likelihood of performance bottlenecks affecting the disk subsystem. By optimizing the disk subsystem, you can make the paging process as efficient as possible. If you have a device with an SSD as the primary disk and a normal hard disk as the secondary disk, moving the paging file is not likely to improve performance.
    • Configure a fixed-size paging file. A paging file that can grow on the disk might encompass fragmented areas of the disk volume. By configuring a fixed-size paging file, you can ensure that the paging file does not encompass fragmented areas.
    • On non-SSD drives, ensure that the disk volume is not fragmented when you create the paging file. If you want to create a fixed-size paging file on a computer that already has a paging file, ensure that you do not create a paging file that encompasses fragmented areas of the disk. Additionally, before you create a fixed-size paging file, you should configure the computer to use no paging, and then defragment the volumes.
    • When you configure the paging file, ensure that its size is sufficient. Recommendations specify that an initial paging file should be equivalent to the amount of installed memory, and a maximum paging file size that is equal to twice the initial value. Consequently, you should create a fixed-size paging file that is equal to or twice the size of the physical memory.
    • Add physical memory to a computer that is paging excessively. If you investigate performance on a computer with a memory bottleneck, you often find that disk performance is low as well. By adding extra physical memory to the computer you can reduce the load on the disk subsystem and thereby improve both memory and disk performance.
  • Implement faster disks. Disk speed is measured in revolutions per minute (rpm), and average seek times are measured in milliseconds. Install disks running 7200 rpm or faster, and select disks with the lowest seek time. On desktop computers, you also can install a disk controller that supports a faster bus type. The first Serial ATA (SATA) standard supports transfer rates up to 150 megabytes per second (MBps) whereas the latest SATA standard supports transfer rates up to almost 2000 MBps. Changing your disk controller and disks that support the new disk controller could improve the disk subsystem performance considerably.

  • Consider using SSDs. SSDs use flash memory technology and have no moving parts. They can operate faster than traditional disks, but they are more expensive. Carefully research the specific vendor and model of disk. Some disks provide higher write performance, and some provide higher read performance. In systems that support multiple drives where SSD cost is a concern, consider a smaller SSD drive to store the OS and a SATA drive for apps and data.

  • Defragment volumes that are used heavily. You can use either the built-in disk Optimize Drives tool or another company’s tools, some of which support the defragmentation of files such as Hiberfil.sys and Pagefile.sys. Windows optimizes drives automatically once a week and will run the proper optimization automatically (defragmenting SATA drives or running TRIM on SSDs).

  • Ensure that you enable write-caching. You can use Device Manager to examine the properties of any installed disks, and to verify that write-caching is enabled.

  • Distribute the memory load across all available disks. If your computer has multiple physical disks, consider distributing disk-intensive activities across these disks. For example, you can install the Windows operating system and applications on one disk, the paging file on another disk, and your data files on a third disk.