Advanced Operating Systems

This is the home page for the "Advanced OS" course. Here, you will find (in a badly-organised form) all the material, slides, and information needed to attend the course

Lessons:

• First lesson: 2018/3/13, 15:00 -> 17:30, at tecip (Acquario)
  • Introduction to the course (in Italian)
  • Something about Real-Time Operating Systems (in Italian)
• Second lesson: 2018/3/21, 14:30 -> 17:00, at tecip (PC room)
  • Quick summary about system architecture and OS kernels (in Italian)
  • Investigating the kernel latency (in Italian): timer resolution latency and non-preemptable section latency
• Third lesson: 2018/3/22, 14:30 -> 17:00, at tecip (White room)
  • More details about the non-preemptable section latency
  • Kernel architectures (and their impact on latency)
  • Recordings (in Italian): part 1 and part 2
• Fourth lesson: 2018/3/28, 14:30 -> 17:00, at tecip (Yellow room)
  • RTOS User space: implementing periodic timers (video in italian)
  • Some tests with Xenomai (slides and video in italian)
  • Some notes about kernel locking
• Fifth lesson: 2018/3/29, 14:30 -> 17:00, at tecip (White room)
  • More details about uKernel systems
  • The relationship between nanokernels and hypervisors
• Sixth lesson: 2018/4/4, 14:30 -> 17:00, at tecip (PC room)
  • Introduction to hypervisors and virtual machine monitors
  • Discussion about trap and emulate
• Seventh lesson: 2018/4/6, 14:30 -> 17:00, at tecip (PC room)
  • Some more discussion about CPU virtualization (x86, ARM, paging)
  • First experiments with Intel VT-x (see example below)
• Eighth lesson: 2018/4/26, 14:00 -> 16:30, at tecip (white room).IMPORTANT: bring your laptop (with Linux and kvm on it) with you
  • Example about trap and emulate (sorry, no video)
  • Example about Intel VT-x
• Ninth lesson: 2018/5/4, 14:00 -> 16:30, at tecip (white room).IMPORTANT: bring your laptop (with Linux and kvm on it) with you
  • Summary about Intel VT-x
  • ...
  • Example about KVM (broken video, I am trying to repair it)
• Tenth lesson: 2018/5/14, 14:00 -> 16:30, at tecip (white room)
• Next lesson: 2018/5/17, 14:00 at tecip (white room)

Slides and references:

• Some references to scientific papers about the arguments described in the course
• A list of possible projects for the exam. Notice: some projects might have "hidden issues"... Contact me when you decide to work on a project.
• Introduction to the course
• Something about Real-Time OSs
• Quick summary about OS kernels
• More about the Kernel Latency
• Some notes on Kernel Architectures for Low Latency
• Some notes about kernel locking
• Some hints for implementing periodic timers
• Some tests with Xenomai
• Comparison between uKernels and Dual Kernels
• Some more details about uKernels
• Some more details nanokernels and hypervisors
• Some slides about CPU virtualization
• Something about more advanced CPU virtualization
• Quick introduction to unikernels
• Slides about unikernels
• Slides about the OSv unikernel
• Slides about unikernel hypervisors
• Slides about unikernels for nfv

Random Source Code:

• Some code showing trap and emulate. Notice that the example "hypervisor" (running in ring 0) just runs the guest code in ring 3... The guest executes a sensitive privileged instruction (mov cr0, edx) that is emulated, and a sensitive non privileged instruction (smswl eax) that cannot be trapped / emulated... Since in theory the two instructions should return the same value, the guest can easily understand that some kind of hypervisor is running! This shows the need for VT-x
• Linux Kernel Module to read some VT-x information
• Linux Kernel Module showing how to use VT-x
  • Basic OS image for testing the modules (built with https://gitlab.retis.sssup.it/l.abeni/BuildCore.git)
• Simple example about KVM
  • Try to handle different VM exit reasons as in this modified test.c (using this modified guest)