barebones

linking, just an exchange of call table. There is very primitive backtrace functionality in the panic function simply by using compiler builtins. No way to convert the addresses to function + offset because there is no symbol table. One cool way to do this is to link the kernel, generate an ELF section that contains only the function symbols, and then append it to the end of your kernel. During initialization you can then use it for backtraces. It's also fairly architecture independent, as you will only have to distinguish between 32- and 64-bit symbols.

e to SSE) end of our stack area.

serspace Linux platform of IncludeOS. I have written a beginners-kernel project where I show that LTO reduces image size to 2/3 from 32kb to 11kb: https://github.com/fwsGonzo/barebones 2. There is a paper showing this linked to in the repo itself. You can at least build the unikernel on linux userspace, so it shouldn't be too hard to debug it while you are creating it. Other than that, debugging is not easy in production just like you say. 3. Traditional hypervisors manage access to hardware all the time, while a new type of unikernel hypervisor wouldn't. It would just sit there after the configuration/startup phase and never be exited into. The number of VMEXITs something has to do for each packet is a good estimator for how performant something is. If the number is zero, then it must be performant. See bareflank and others. I can't elaborate further because it's an area of research, and I'm not an expert. Afaik there is nothing like this running in production yet, even if we can prove that it's possible to run exitless and with no kernel privileges! Maybe next year we will know more. 4. We absolutely support threads, its just not working right now. We also have an SMP API that is quite good, and the virtual CPUs are scheduled on the host side. We also have fibres. While we do have tests, I don't know the state of things. We have so many other things going trying to make the OS stable in a production environment. I couldn't find a single thing proving my assertion when I made a quick search, so I will just retract until I can find it again. As I'm sure you know unikernels tend to have a single address space, which removes the need to do a full context switch. 5. I don't think our customers will be deploying containers. Rather, I think they will be running hundreds of instances per physical host in their private clouds. Instances will act as Internet gateways, firewalls etc. Some network function. That is the stage we are at now. I really don't see containers being used after the binaries are built, but I could be wrong.