• Shared resources include memory, global variables, files, and databases.
• A race condition occurs when two or more processes attempt to update shared data at the same time, leading to unexpected results. Example: Two bank transactions modifying the same account balance simultaneously without synchronization may lead to incorrect final balance.

It could be visualized using the pseudo-code below

do{ flag=1; while(flag); // (entry section) // critical section if (!flag) // remainder section} while(true);

do{ flag=1; while(flag); // (entry section) // critical section if (!flag) // remainder section} while(true);

A good critical section solution must ensure:

1. Correctness - Shared data should remain consistent.
2. Efficiency - Should minimize waiting and maximize CPU utilization.
3. Fairness - No process should be unfairly delayed or starved.

• At most one process can be inside the critical section at a time.
• Prevents conflicts by ensuring no two processes update the shared resource simultaneously.

• If no process is in the critical section, and some processes want to enter, the choice of who enters next should not be postponed indefinitely.
• Ensures that the system continues to make progress rather than getting stuck.

• There must be a limit on how long a process waits before it gets a chance to enter the critical section.
• Prevents starvation, where one process is repeatedly bypassed while others get to execute.

Example Use Case: Older operating systems or embedded systems where simplicity and reliability outweigh responsiveness.

A simple solution to the critical section can be thought of as shown below,

acquireLock();Process Critical SectionreleaseLock();

acquireLock();Process Critical SectionreleaseLock();

A thread must acquire a lock prior to executing a critical section. The lock can be acquired by only one thread. There are various ways to implement locks in the above pseudo-code.