Interactive Clock page replacement simulator with circular clock-face visualization, hand sweep, reference bits, decision explainer, and step history.
Presets
Reference string
Step 0 / 0
Idle
Press play or step forward to begin. Clock arranges frames in a ring. On a hit, the page's reference bit is set to 1. On a fault, the hand sweeps clockwise: bit = 1 means second chance (clear and advance), bit = 0 means evict.
Clock buffer · the purple hand scans clockwise for a page with bit = 0
1recently used — second chance0eligible for eviction