NVMeDirect is a user-space I/O framework for NVMe SSDs, which allows user applications to access the storage device directly. This will enable various application-specific optimizations on NVMe SSDs. For further details on the design and implementation of NVMeDirect, please refer to the following paper.

• Hyeong-Jun Kim, Young-Sik Lee, and Jin-Soo Kim, "NVMeDirect: A user-space I/O Framework for Application-specific Optimization on NVMe SSDs," Proceedings of the 8th USENIX Workshop on Hot Topics in Storage and File Systems (HotStorage), Denver, Colorado, USA, June 2016.

To build the kernel module and shared library,

$ make

To install the kernel module, shared library, and header file,

$ sudo make install

This will install the following files:

• nvmed.ko in /lib/modules/$(shell uname -r)/extra

• lib_nvmed.h in /usr/local/include

• libnvmed.so in /usr/local/lib

• nvmed_admin in /usr/local/bin

To load the NVMeDirect module into the kernel,

$ sudo modprobe nvmed

The root can restrict the users of the NVMeDirect framework and the number of I/O queues per user using the user-space tool, nvmed_admin.

$ sudo nvmed_admin /dev/nvme[device id]n[namespace id] set [user name] [queue count]

Finally, link your program with the NVMeDirect library and run!

Please refer to the NVMeDirect-APIs.md file.

The NVMeDirect framework is being currently maintained by Computer Systems Laboratory in Sungkyunkwan University, South Korea. NVMeDirect is an on-going work and we welcome your contribution and feedback. If you have any questions or suggestions, please contact the following people.

• Hyeong-Jun Kim (hjkim@csl.skku.edu)

• Jin-Soo Kim (jinsookim@skku.edu)