Das Video kommt von YouTube: erst beim Abspielen verbindet sich die Seite mit YouTube (Google).
Operating systems - Critical sections
Das Wichtigste aus dem Video
Tipp auf eine Zeit – das Video springt genau dorthin.
Transkriptautomatisch erstellt · 12 Zeilen
- Okay. So let's try to look to talk a little bit about critical sections in operating systems. Uh the idea of critical sections is that if I have at
- least two processes that has they that both both have the same resources they may change at the same time uh some resource for example a list.
- Let's take an example taking out a node in the list. Deleting a node and if I have two processes that work on that list at the same time they may delete a
- node and instead simultaneously instead of deleting two nodes because two processes worked on that list. What happened is that only
- one node was deleted even though two processes said or did a delete operation and this is not okay. This happens because the critical
- section is a section in which two processes work on a same resource. It means that when we are looking on a code of two processes there may be
- critical and non-critical sections. And when we are talking about a critical section, it's section that do something to a resource without doing something to
- a resource that is shared between the two processes. This is not a critical section. So in those critical sections I need to make sure
- that only one processes at a time work on it. I mean if one processes one process do a delete and one process do add or something like this to the same
- resource that is shared between the processes I need to make sure that at the same time only one process is working when he's doing it because if
- there will be a context switch at a time he works on the resource there may be weird things that happen as I mentioned so this is the idea of a critical
- Intersection between at least two processes that work on a shared resource.
Zum Nachlesen
Kritischer AbschnittKritische Abschnitte bestehen aus mehreren Einzelanweisungen, deren Zwischenergebnisse inkonsistente Zustände darstellen, auf die die anderen Threads keinen …
WettlaufsituationEine Wettlaufsituation, aus dem Englischen auch Race Condition (deutsch Wettlauf-Bedingung) oder Race Hazard (deutsch Wettlauf-Risiko), mitunter auch …
MultithreadingMultithreading (englisch wörtlich für Mehrfädigkeit oder auch Mehrsträngigkeit und, weiter übertragen, die Nebenläufigkeit) bezeichnet in der Informatik das …
InterprozesskommunikationDeadlocks. Bearbeiten. → Hauptartikel: Deadlock (Informatik). Eine Menge von Prozessen befindet sich in einem Deadlock-Zustand, wenn jeder Prozess aus der …