Topic starter
What is cache hit ratio?
It’s the percentage of requests served from cache.
Higher = better performance + lower server load
Ways to improve cache hit ratio
1. Cache more static content
Make sure all static assets are cached:
- Images (
.jpg,.png,.webp) - CSS & JS
- Fonts
Configure your CDN (like Cloudflare or Amazon CloudFront) to cache these aggressively.
2. Use proper Cache-Control headers
Control caching behavior using headers:
</>http Cache-Control: public, max-age=31536000
public→ CDN can cache itmax-age→ how long to cache
Longer TTL = fewer cache misses
3. Use versioning (cache busting)
Instead of changing file content with the same name:
Bad: style.css
Good: style.v2.css
This allows you to:
- Cache files for a long time
- Avoid unnecessary invalidation
4. Avoid unnecessary cache invalidation
- Don’t purge cache too often
- Only invalidate specific files when needed
Frequent invalidation = more cache misses
5. Normalize URLs
Different URLs = different cache entries
❌ Example: /product?id=1 /product?id=1&utm=ads
👉 CDN may treat them as different
✅ Solution:
- Ignore query params (like tracking params)
- Use URL normalization rules
6. Cache API responses (when possible)
Even dynamic data can be cached:
- Use short TTL (e.g., 30–60 seconds)
- Cache GET requests
Great for:
- Product listings
- News feeds
7. Use stale-while-revalidate
Serve cached content even if slightly outdated:
</> http Cache-Control: max-age=60, stale-while-revalidate=300
Benefits:
- Users get fast responses
- CDN updates content in background
8. Enable compression & optimization
While not directly increasing hit ratio:
- Reduces payload size
- Improves perceived performance
9. Geo-distribute content effectively
Make sure CDN edge locations are used properly:
- Choose a good CDN provider
- Enable global distribution
10. Monitor and analyze
Track metrics like:
- Cache hit ratio
- Cache miss rate
- Origin requests
Use CDN dashboards to optimize continuously
Answer Summary :
“To improve cache hit ratio, I would cache static assets aggressively, use proper cache-control headers, implement versioning for cache busting, avoid unnecessary invalidation, normalize URLs, and cache dynamic content where possible.”
Posted : 05/04/2026 8:52 am
