Interview Q&A / Operating Systems
Operating Systems interview questions
Processes, threads, scheduling, memory and deadlocks, in plain words.
Prefer rapid revision? Practise Operating Systems short interview answers →
- How does the Banker's algorithm decide whether a resource request is safe?
It pretends to grant the request, then checks whether some order exists in which every process can still finish with the resources left. If such a safe sequence exists, the request is granted; otherwise it waits.
AdvancedQuick answer2 min read - What is the Test-and-Set instruction and how does it provide mutual exclusion?
Test-and-Set is a hardware instruction that atomically reads a memory flag and sets it to 1. If it returned 0, the caller got the lock; if 1, someone else holds it. Because it is one indivisible step, two threads cannot both see 0.
AdvancedQuick answer1 min read