TTFB / Compression / Cache-Control Checklist

Problem

The site feels slow or static assets are not optimized for repeat visits.

Symptoms

• HTTP diagnostics show high TTFB.
• Content-Encoding is missing.
• Cache-Control is absent or too weak for static assets.

Top 3 Causes

1. The origin is slow to respond - Application work, database calls, or upstream dependencies add latency.
2. Compression is disabled - Text assets are sent uncompressed.
3. Caching strategy is missing or weak - Static assets are downloaded repeatedly because cache headers are not set properly.

Diagnose with DechoNet

• HTTP Check to inspect TTFB, Content-Encoding, and Cache-Control in one pass.

Resolution Checklist

• Investigate origin processing time and upstream dependencies for slow routes.
• Enable gzip or brotli for text-based assets.
• Set an appropriate Cache-Control policy for static assets.
• Separate HTML caching policy from long-lived asset caching policy.
• Re-run HTTP Check and confirm TTFB, compression, and cache headers have improved.

When to Escalate

• Escalate beyond the web server if the bottleneck sits in databases or upstream services.
• Coordinate with platform owners if CDN policy and origin cache policy conflict.