# Performance benchmarks for CDN and MediaTailor integrations
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When optimizing your AWS Elemental MediaTailor CDN integration, aim for these performance benchmarks. These targets apply to all MediaTailor implementations including SSAI, channel assembly, and combined workflows:

Cache Hit Ratio Targets  
Content segments: greater than 95% cache hit ratio  
Ad segments: greater than 90% cache hit ratio  
Manifests: Not applicable for SSAI (should not be cached for personalized ad insertion); 85%\$1 for channel assembly

Latency Benchmarks  
Manifest request latency: less than 100ms (P95)  
Content segment delivery: less than 50ms (P95)  
Ad segment delivery: less than 75ms (P95)  
End-to-end startup time: less than 2 seconds

Origin Load Metrics  
Origin requests per viewer: less than 0.1 requests per minute per viewer  
Origin bandwidth per viewer: less than 5% of total viewer bandwidth

Error Rate Targets  
Manifest errors: less than 0.1%  
Segment errors: less than 0.01%  
Player-reported rebuffering: less than 1%

Scalability Benchmarks  
Support for 10 times the normal traffic during peak events without degradation  
Ability to handle greater than 1000 requests per second per channel

Use Amazon CloudWatch metrics to track these performance indicators. For detailed monitoring instructions, see [Set up monitoring tools](cdn-monitoring.md#cdn-monitor-tools-setup).