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• critical section a sequence of code that needs to execute in an atomic fashion (un-interruptible), or the concurrency breaks.
• race condition situation where the outcome, and often also the correctness, of a program depends on how the threads of the program happen to be scheduled.
• context switch he operating system switches execution from one thread to another. One thread is temporarily suspended, and another one starts execution. Once the suspended thread resumes, it continues from where it was suspended
• non-preemtive scheduling tråd som kör kan inte avbrytas utan att släppa cpun frivilligt
• pre-emption point based tråden som kör kan avbrytas vid vissa punkter i programmet
• pre-emptive scheduling tråden som kör kan avbrytas när som helst av schemaläggaren
• mutual exclusion Exekvering av en kod i en kritisk sekvens får inte flätas ihop med någon annan tråds kodsekvens.
• deadlock en låsning i programmet då olika trådar väntar på varandra
• prioritetsinversion när en högre prioriterad tråd blir blockerad av en lägre prioriterad kod
• prioritetsarv när en lägre prioriterad tråd ärver prioriteten från en högre prioriterad tråd
• critical instance the worst possible case for jobs wanting to execute in a system. In particular, when they all arrive at the same time
• static scheduling off-line approach in which you manually generate a fixed execution table or calendar. The table states which thread should run at any given moment. The table repeats cyclically
• dynamic scheduling s applied ad-hoc, threads are scheduled on-line either according to priorities or following a round-robin approach

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