How does the Proxy Cache Key Lookup actually happen?

I am using part of the request_body as the Cache_key in setting up the Proxy_cache_key and I was wondering how the actual lookup / matching of the Cache would occur? >From the documentation, it looks like it's a MD5 encryption of the Cache Key that I set. Does that mean the cache_key lookup woul

Cache Hit Latency for large responses.

Context: I am currently using nginx to serve as a Response Cache Proxy in order to shim-out (isolate) network latency while running some performance related tests. The Perf Tests are comprised of 50 repetitions of the same set of requests. => I have been able to successfully set-up the proxy_cach