How to get a deadlock for experiments?

Deadlock (mutual blocking) occurs when two or more processes or transactions wait for resources held by each other, and none of them can continue.

To create a deadlock for experimental purposes, you can set up a situation where two processes block resources in different orders. For example, in a database:

1. Process A locks table or row 1.
2. Process B locks table or row 2.
3. Process A tries to lock table or row 2 and waits.
4. Process B tries to lock table or row 1 and also waits.

As a result, both processes wait for each other — a deadlock occurs.

Example in SQL (PostgreSQL):

-- In session 1
BEGIN;
LOCK TABLE table1 IN ACCESS EXCLUSIVE MODE;
-- Waiting

-- In session 2
BEGIN;
LOCK TABLE table2 IN ACCESS EXCLUSIVE MODE;
-- Waiting

-- In session 1
LOCK TABLE table2 IN ACCESS EXCLUSIVE MODE; -- gets blocked

-- In session 2
LOCK TABLE table1 IN ACCESS EXCLUSIVE MODE; -- gets blocked

For experiments, you can run such transactions in parallel and observe system behavior, logs, and deadlock detection mechanisms.

Important: In real systems, deadlocks should be avoided, but for experiments, they can be created in a controlled and isolated environment.