How to maintain and manage Intel® Optane™ memory for best performance
The options in the operating system for defragmenting the HDD are no longer available after installing Intel® Optane™ memory.
When a storage drive is paired with an Intel® Optane™ memory device it becomes an Intel® Optane™ memory volume, and it looks like one drive instead of two. The drive is then maintained and managed for best performance by the Intel® Rapid Storage Technology (Intel® RST) driver and software.
Disable acceleration before defragmenting the storage drive.