View All num of num See all Photos Netflix This employer has taken extra steps to respond to reviews and provide job seekers with accurate company information, photos, and reviews. Interested for your company?Learn More. www.netflix.com Employer Engaged Overview Reviews Salaries Interviews Jobs Photos Benefits 448 Reviews 555 Salaries 289 Interviews Follow Add Review or Salary Follow Add Review or Salary Interview Question Senior Software Engineer Interview Netflix design garbage collection system Tags: See more , See less 8 Answer Add Tags Answer Interview Answer 1 Answer ▲ 0 ▼ The simplest concept is (naive) `mark and sweep`: one walk through the graph of objects (starting from the `root` objects that are known to be reachable), `marking` all the objects reached in the walk; then a `sweep` through all existing objects, deleting all the unmarked ones (and unmarking the marked ones to be ready for the next cycle). Many improvements are possible, esp. to allow incremental or concurrent GC, but they take quite a bit longer to explain;-). Alex on May 19, 2013 Add Answers or Comments To comment on this, Sign In or Sign Up.