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We are sending a HTTP WCF request to a 3rd party system hosted on our servers and were experiencing a significant delay between sending the request and getting the response. The 3rd party are claiming that they complete their work in a few seconds but in fiddler I can see a significant gap between the ServerBeginResponse and the GotResponseHeaders.

Now I'm not sure what could account for this delay? Could someone explain what the ServerBeginResponseand the GotResponseHeaders timers in Fiddler actually mean?

Fiddler statistics tab screenshot

EricLaw
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Liam
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  • Greetings, I am having an issue that seems strikingly similar, but I can't nail down what is causing the delay. Were you able to solve this or determine the cause? – John Russell Jun 07 '13 at 19:19

1 Answers1

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The timers mean pretty much exactly what they say-- The ServerGotRequest timer is set when Fiddler is done transmitting the HTTP request to the server. The GotResponseHeaders timer is set when Fiddler has read the complete set of response headers from the server.

In your screenshot, there's a huge delay between ServerBeginResponse (which is set when the first byte of the server's response is returned) and GotResponseHeaders which suggests that the server spent a significant amount of time in completing the return of the HTTP response headers.

If you send me (via Help > Send Feedback) a SAZ capture of this traffic, I can take a closer look at it.

EricLaw
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  • Hi Eric, thanks for you help on this. I've sent the saz. It could simply be that the service is taking a very long time to return. I just want to eliminate all other possibilities before I start pointing fingers! – Liam Feb 15 '13 at 08:51
  • @Liam - What was the result of this? Does the long gap mean it was taking the 3rd party a long time to complete or an issue on the server processing the header? We are encountering a similar problem. – Belogix Jan 16 '14 at 11:58
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    @Belogix, for us, the issue ended up being HTTP throughput. The connections were queuing on the server and we couldn't get them though fast enough. We've since increased the number of servers and improved our load balancing reducing this issue. Hope that helps – Liam Jan 16 '14 at 12:01
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    @Liam - Great, thank you and for the VERY fast reply on an older thread! Much appreciated. – Belogix Jan 16 '14 at 13:16
  • Hi Eric, I am also facing a similar situation where according to my understanding request is reaching the server but the time shown in GotResponseHeaders is almost 6 minutes later. ClientConnected: 22:34:40.246 ClientBeginRequest: 22:34:41.338 GotRequestHeaders: 22:34:41.338 ClientDoneRequest: 22:34:41.697 DNS Lookup: 0ms TCP/IP Connect: 0ms HTTPS Handshake: 0ms ServerConnected: 22:34:40.246 FiddlerBeginRequest: 22:34:41.697 ServerGotRequest: 22:34:41.697 ServerBeginResponse: 22:34:41.697 GotResponseHeaders: 22:41:20.745 ServerDoneResponse: 22:41:20.745 – Paras Chaudhary Aug 31 '20 at 10:23
  • Hi Eric, Please also suggest how can I share the SAZ file to you? – Paras Chaudhary Aug 31 '20 at 10:31
  • Email link in the header of https://ericlawrence.com/ – EricLaw Sep 02 '20 at 19:15