What are the caching mechanisms in Chrome browser?

Browser Caching Mechanism

Chrome browser uses multiple caching mechanisms to improve page load speed and reduce network requests.

Cache Types

1. Strong Cache

   • Controlled by HTTP headers: Cache-Control and Expires
   • Cache-Control: max-age=3600 means cache for 1 hour
   • Higher priority than negotiated cache

2. Negotiated Cache

   • Controlled by HTTP headers: ETag and Last-Modified
   • ETag: Unique identifier of resource content
   • Last-Modified: Last modification time of resource
   • Needs to verify with server if resource has changed

3. Service Worker Cache

   • Offline caching capability
   • Can intercept network requests
   • Provides more granular cache control

4. Memory Cache

   • Stored in memory, invalidates after page closes
   • Fast access speed but limited capacity

5. Disk Cache

   • Stored on disk, can persist long-term
   • Large capacity but relatively slower access speed

Caching Strategy

• Static Resources: Use strong cache with long expiration time
• HTML Files: Use negotiated cache to ensure latest content
• API Responses: Set appropriate caching strategy based on business needs

Cache Priority

1. Service Worker Cache
2. Memory Cache
3. Disk Cache
4. Network Request

Practical Applications

• Use version numbers or hash values to update static resources
• Set Cache-Control headers appropriately
• Use Service Worker for offline access