Microsoft provides a chart to explain which optimization feature is best for your drive. The following chart will give specifics on the differences between thinly provisioned drives and VHDs, which is helpful but geared toward a techie rather than the common user.

  • Defragment: Rearranges the files of a specific hard drive in a contiguous order.
  • Trim Optimization: Tells the backing storage which data blocks are out of use. This allows the storage to then optimize performance and space for future use.
  • Slab Consolidation: This process is used primarily in thinly provisioned drives. It rearranges data from sparsely populated slabs to densely populated slabs.

There are a series of changes in Windows 7 Disk Defragmenter tool has been changed again in Windows 8.1 and Windows 10. It got some new inner workings and a new name: Optimize Drives. As a result, defragmenting drives in Windows 8.1 and Windows 10 is a bit different from what it used to be in previous versions of Windows.

When defragmenting a disk partition, Windows rearranges the files stored on the disk so that they occupy contiguous storage locations. Doing this increases the access speed to your files by minimizing the time required to read and write files to and from the disk and by maximizing the transfer rate. You might also see improved startup times. Defragmentation should be done especially when both your operating system and your most commonly used applications are installed on the same drive and the operating system gets slower over time. Defragmentation is especially useful when dealing with traditional hard disk drives, also known as HDDs.

Do not defragment SSDs (Solid State Drives) or USB drives. These types of drives have a different way of allocating files and they have a limited number of read/write cycles before they stop working. Hence, defragmenting them will decrease their lifespan. Given the high read and write speeds provided by SSDs, you shouldn't encounter slowdowns anyway, so there's no reason to defragment them. Windows knows about this and it doesn’t defragment SSDs by default.

How to analyze and defragment your drives in Windows

In the Status section of the Optimize Drives app window you see a list with all the drives that exist on your Windows computer or device. For each drive you see its name, drive letter, the media type (solid state drive, hard disk drive, removable drive, etc.), when the defragmentation was last run and the current status, meaning the fragmentation status of each partition. The list includes hidden drives like the Recovery drive that is automatically created when installing Windows.

To get an updated status of each partition and see if it needs to be optimized, select the partition you are interested in and then click or tap Analyze. Optimize Drives will then analyze the partition and tell you whether you need to optimize it or not. If you want to select multiple partitions, hold the Ctrl key pressed while clicking the partitions to analyze. Then, click or tap Analyze all.

After running the disk analysis, you can see how fragmented the partition is. This information will help you decide whether you need to defragment the disk or not. It is advisable to optimize drives whenever their fragmentation status goes beyond 20%.

To defragment a partition, select it and press Optimize. You can also hold the Ctrl key while clicking the partitions to optimize. Then, click or tap Optimize all to run the optimization on multiple partitions at once. While the tool analyzes and optimizes the selected partitions, you will see the running status in the Last run column and the completion percentage in the Current status column. If you want to interrupt the process, press Stop.


After running the disk analysis, you can see how fragmented the partition is. This information will help you decide whether you need to defragment the disk or not. It is advisable to optimize drives whenever their fragmentation status goes beyond 20%.

To defragment a partition, select it and press Optimize. You can also hold the Ctrl key while clicking the partitions to optimize. Then, click or tap Optimize all to run the optimization on multiple partitions at once. While the tool analyzes and optimizes the selected partitions, you will see the running status in the Last run column and the completion percentage in the Current status column. If you want to interrupt the process, press Stop.

One of the good things about this tool is that you can use the computer to do other things while running any of the available operations. Therefore, don’t wait for the defragmentation to be over before doing your work on your Windows computer. Or you can use NEPTUNE SYSTEMCARE 2017 to help you out.