PMDK for Windows
Throughout 2016 a team of engineers from Microsoft, Intel, HPE and HPI have been working to port the PMDK project to Windows and we are happy to announce that Technical Preview release is now available!
Our main goal in porting the library was to make it as easy as possible for developers to use the library in both Linux and Windows environments. To meet this goal, we focused on these elements as we undertook the effort:
- Maintain common API
- Reuse existing library code
- Reuse as much test code and semantics as possible
Our efforts have paid off! We are labeling this a Technical Preview because we have yet to add UNICODE support for paths which is generally considered a required item for Windows components. However, the library is fully functional today provided wide characters are not used. Here are some of the more interesting points about the Windows port:
Common Code
You will only find a few areas where there are Windows specific files and/or directories in the repository and there were added only in cases where there was really no other choice; OS specific implementations of locks and threads for example. Use of OS compilation switches, ifdef WIN32, are minimized and only used where breaking out the implementation would cause either performance or readability issues. Beyond items like those, everything else is common.
Test Code
The unit test framework for the original library implementation is a combination of BASH, Perl and C. Although using native BASH in Windows may happen sometime in the near future, the group chose to go with Powershell for the Windows port. The majority of the C code is common minus a few minor tweaks here and there so basically anywhere you find a BASH script controlling a test under Linux you can find the equivalent Powershell script under Windows, this includes the unit test framework as well as RUNTESTS.SH (RUNTESTS.PS1). The syntax and output of the scripts are nearly identical.
Tools
To build the Windows versions, simply use Visual Studio to open up the PMDK.SLN file in the source directory and build the debug and release versions and you are ready to go. Details are in the README files.
The Windows unit tests are executed automatically when a pull request is made, Reviewable is still used for reviews however AppVeyor controls the build and test execution instead of Travis.
As part of the port, the team used Trello to track our backlog and will continue to do so until the UNICODE work is complete at which time any Windows issues will be visible right alongside Linux issues in Github. The Trello webpage for the porting effort is publicly available at: PMDK for Windows
Windows Non-Volatile Memory Support
Obviously PMDK isn’t much use under Windows without native NVM support. The following two videos provide a great overview of Windows NVM capabilities:
- Using Non-volatile Memory (NVDIMM-N) as Block Storage in Windows Server 2016
- Using Non-volatile Memory (NVDIMM-N) as Byte-Addressable Storage in Windows Server 2016