Glossary · Performance
Latency
The delay between sending a request through a proxy and getting a response, driven largely by physical distance to the exit.
Latency is the waiting, the round trip between your request leaving and the answer arriving, measured in milliseconds. A proxy always adds some, because your traffic now takes a detour through the exit before reaching the destination, and the size of that detour is mostly geography.
Distance is the dominant term. An exit in the next city adds little; one on another continent adds the unavoidable cost of light crossing an ocean and back, which is why a proxy's location is a performance decision as much as a targeting one. Datacenter exits also tend to beat residential and mobile on raw latency because they sit on better-connected infrastructure.
Whether it matters depends on the workload. For bulk scraping, throughput across many parallel connections matters more than any single request's latency; for anything interactive or sequential, latency is felt directly, and the shortest honest path is an exit near the target.
How HProxy handles it
We only quote a representative latency figure on a country page when our own vantage point can time that country's pool fairly; for distant countries we report composition and uptime instead of a number the ocean would distort.
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