HttpUrlConnection - odd delays

Question

We have one customer who sends us thousands of web service requests per minute, and what we're seeing with all of their requests specifically is that the HTTP body comes across the wire, then there is a 150-250ms pause, and then the SOAP body is sent.

Being that the header knows the size of the request, I can rule out that this delay is caused by processing needed to generate the request itself.

Based on the user agent, I can determine that they're using Java 1.5, with HttpsUrlConnection. I don't have access to their code (yet), but I'm wondering if people have seen this behavior or not with poorly written code?

My side: A set of Apache web servers, that are front-ended with load balancers, firewalls, ... those web services take requests and use mod_proxy to send them back to Tomcat application servers.

(Again, this behavior is only seen with this one client, so I have doubts that something on my side is causing this...)

Answer 1

Ended up being a router on my customer's edge was completely saturated/overloaded, adding 400ms+ of latency.. So looks like something where the complete request couldn't be sent quick enough. We have reproduced this same behavior adding 400ms of latency with tcpproxy.

Sometimes it's the most obvious explanation, I guess...