Project caching scheme - expiration policy

Expiration Policy

• effect
  • save space
    
  • Weak for data consistency
    
• Expiration Policy
  • Timing expired
    • Low efficiency, each data needs to set the timer counts
  • Inert expired
    • At query time, before going to check the validity of data, if expired, nil is returned, and delete outdated data
  • Regular expired
    • Every 100ms, withdrawing a portion of the random verification data expires, if expired, the data deleted
• redis choice
  • + Inert expired expire periodically (every 100ms to set the expiration time of random data query and deletion of expired data)