Such action might or might not, depending on the circumstances, remove the deadlock.
Most data-base systems have the ability to roll back transactions that fail, and a data-base management
system may provide for rollback in the face of deadlocked access to data-base tables and rows. In fact, modern
data-base management systems are the most likely application area to find implementations of deadlock detection
and recovery.
In the end, it may be best for the system to simply announce that a deadlock has occurred and let the
operator take some action the operator thinks appropriate.
Deadlock detection is potentially expensive of computing time, especially if run frequently, and the question
of what action to take when a deadlock occurs is usually too difficult to automate. As a result, general-purpose
operating systems almost never try to manage deadlock. On the other hand, data-base management systems
often do try to detect deadlocks and recover from them within the narrower purview of data-base management.
SCHEDULING
One of the very most important tasks of an operating system is to schedule processes and threads for execution.
In the early days of computing, the programmer would load the program into memory somehow (front panel
switches, paper tape, etc.
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