operating system - Trouble understanding preemptive kernel -


how preemptive kernel lead race conditions? if process preempted i.e. isn't kicked out of critical section . understanding race condition when several processes try access , manipulate resources concurrently right. have trouble grasping concept

a preemptive kernel can start , stop threads @ point. means threads don't coordinate accesses through locks , critical sections end in race conditions.

the other form of multithreading cooperative multithreading, threads can stopped @ points explicitly offer yield processor. helps prevent race conditions because threads not interrupted @ random unexpected points in processing.

the downside of cooperative multithreading thread written not yield can hog processor, , why modern operating systems use preemptive multithreading rather cooperative multithreading.


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