• Contact: tech-kern, tech-userlevel
• Mentors: Antti Kantee
• Duration estimate: 3 months

Currently, the puffs(3) interface between the kernel and userspace uses various system structures for passing information. Examples are struct stat and struct uucred. If these change in layout (such as with the recent time_t size change), old puffs servers must be recompiled.

The purpose of the project is to:

• define a binary-independent protocol
• implement support
• measure the performance difference with direct kernel struct passing
• if there is a huge difference, investigate the possibility for having both an internal and external protocol. The actual decision to include support will be made on the relative complexity of the code for dual support.

While this project will be partially implemented in the kernel, it is fairly well-contained and prior kernel experience is not necessary.

If there is time and interest, a suggested subproject is making sure that p2k(3) does not suffer from similar issues. This is a required subproject if dual support as mentioned above is not necessary.