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concurrency

Race Conditions

A race condition occurs when the correctness of a program depends on the relative timing of concurrent operations. When multiple threads read and write shared state without proper synchronization, the final result becomes unpredictable. Race conditions are notoriously difficult to debug because they may only manifest under specific timing conditions. The fix is to identify critical sections and protect them with appropriate synchronization primitives.

Use Cases

  • •Preventing double-spending in concurrent financial transaction processing
  • •Ensuring atomic read-modify-write cycles on shared counters or balances
  • •Avoiding lost updates when multiple users edit the same document
  • •Protecting check-then-act patterns like lazy initialization

Visualization

INITIALcountervalue = 0Thread 1idleThread 2idle
Speed:1x
Two threads will each increment a shared counter. Expected result: 2.Step 1 / 7

Implementation

Output

Click "Run Code" to see output...