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I make JSON API and when measuring performance there's this strange thing. When doing XDEBUG_PROFILE, request processing takes about 100 ms. But browser network panel says it's always 1 - 1.5 seconds. Why so big difference and how do I know what causes it?

System is GNU/Linux, Apache 2.2.17

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Perhaps latency? – tjameson Apr 8 '11 at 10:32
@tjameson Requesting small static files from same server takes about 150 ms. – Kuroki Kaze Apr 8 '11 at 10:41

Profiling code will give you the time to compile/run code.

Browser network metrics, will give you the DNS + TCP + HTTP ( + profiled code) steps time.

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If i'm doing CURL from the same server (console) I see the response time is ~1.5 seconds after request. So it's not latency and not a network issue. – Kuroki Kaze Jun 6 '11 at 10:29

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