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Minute takers according to this page
March 9
Participants:
Minutes
March 2
Participants:
- Artem
- Peter
- Gunnar
- Philippe
Minutes
- Xen project status & current state from Artem
- Walkthrough AVPS 2.0 prioritization tickets
- Lots of discussions on plans / purpose / and various input to the Hypervisor Project overall – initiated by Peter, filled in by Artem.
February 17, 21, 28
Minutes pending
February 10
Participants:
- Kai
- Dmitry
- Adam
- Gunnar
Whitepaper:
- Main subject as agreed: "Why is Virtualization needed?"
- But should we also include challenges that are added as a result of choosing virtualization?
For example shared-memory as discussed in the comment by Michael on Whitepaper - first private draft text
Discussing shared memory challenges:
Locking implies timing interference. Lock-free implementations are complex but important. Can hardware support be provided to improve the implementation of shared memory implementation?
Kai: You would sacrifice isolation if different criticality functions access the same memory.
Adam: For video the approach be fine as long if data corruption is less of a concern. Depends on the use cases of course.
For sharing it is required to consider hardware support for making some access read-only to guarantee that non-critical software cannot change the memory values of critical software.
Gunnar: What about if there is only one writer (critical task) and multiple readers. Can non-critical readers negatively affect critical software by starving the memory bandwidth or similar?
Adam: Generally starving is not possible due to hardware setup. A worst case analysis would be needed.
Adam: Hardware counters usually exist that can enforce budgets on the memory usage. Usually two counters or so, the number of counters might not be enough.
Kai: How do the lock-free implementations perform in worst-case situations?
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