The dining philosophers problem is a computer science thought experiment using a circular table with five philosophers and utensils. It illustrates synchronization problems and the difficulty of preventing deadlock. Solutions involve creating algorithms to regulate when philosophers eat, think, or use utensils. The problem was first expressed by Edsger Dijkstra in 1965 and has undergone changes since.
The dining philosophers problem is a thought experiment or an example used in computer science. The issue uses an analogy to illustrate synchronization problems that can occur when computers share resources. Computer scientists use philosophers’ dining problems to teach students the algorithms used to solve these problems.
The scenario of the dining philosophers problem is a circular table at which five philosophers are seated. In the center of the table is a bowl of noodles or other food. Each philosopher has a fork or rod on either side, meaning there are five forks or rods in total. To eat, a philosopher needs two utensils. Every philosopher must also spend some time thinking, and cannot think and eat at the same time. At the heart of the dining philosophers problem is the difficulty of preventing deadlock.
The stalemate in this problem occurs when philosophers put themselves in a position where they can neither think nor eat. For example, if each philosopher took the utensil to his left, no one could eat, because all utensils would be in use but no philosopher would have two. To allow all philosophers to eat, the student must create an algorithm that ensures that some philosophers eat while others think. This allows both eating and thinking to continue without stalling.
There are a number of possible solutions to the philosophers dining problem. One solution involves creating a sixth character, the waiter, who grants or denies the philosophers permission to pick up forks. Others involve regulating the order in which philosophers pick up and set down their forks to maximize availability. Others involve telling philosophers to check if their neighbors are eating before trying to eat. In essence, every solution involves developing a set of rules, called an algorithm, that govern when philosophers think, eat, or pick up and put down their utensils.
The dining philosophers problem was first expressed by the Dutch computer scientist Edsger Dijkstra in 1965 as an exam question for students. Since then, the issue has undergone a number of changes. It appears in a number of slightly different formats, some of which only change the details of the story, but others which further limit the problem to demonstrate difficult concepts. The most common modern version was created by Tony Hoare.
Protect your devices with Threat Protection by NordVPN
