I am trying to verify that the timings in the Network panel are accurate. This is for an application performance analysis utility I am developing for a client.
I am using a network emulator to force additional artificial latency into the network. My test preconditions are to clear the windows DNS (ifconfig /flushdns), and set Firefox not to cache any DNS entries (network.dnsCacheExpiration and network.dnsCacheEntries both set to 0). I am trying to validate what I see in the net panel is correct by using Wireshark to see the actual network traffic. The results prove that the DNS lookup and connect are being lumped into blocking time. I am using a static image from my own website to test. I am adding about 225ms of RTT latency. http://www.eperformancegroup.com/blog/wp-content/plugins/slideshow-gallery/views/default/images/left.gif?test=xxx The FB network panel shows blocking of 843ms, waiting of 283ms Wireshark shows DNS lookup time of 567ms Wireshark shows TCP connect of 275ms. Add in DNS time and the total is 842ms. Wireshark shows response time of 284ms So - the total times match up - but the network panel lumped both the DNS time and the TCP connect time into blocking. Can this be easily fixed / is there a workaround I might use? HAR file is attached. FF 33.1, Firebug 2.0.6 In a repeat test, I can confirm that this is repeatable. FB net panel shows blocking of 620ms, wait of 284ms "timings": { "blocked": 620, "dns": 0, "connect": 0, "send": 0, "wait": 284, "receive": 0 }, For the repeat test: Wireshark shows DNS of 341 ms Wireshark TCP connect time of 274 ms - a total of 615ms wireshark shows response time of 283 ms <https://lh5.googleusercontent.com/-d9v5R_kJSK4/VGGA2Xhq64I/AAAAAAAAAAM/ROyp-c_ZgGM/s1600/FB%2Bnetwork%2Bpanel.png> <https://lh5.googleusercontent.com/-1_ADrfv5OKQ/VGGA5xNczhI/AAAAAAAAAAU/Hj1V73S8Ubc/s1600/DNS%2Blookup%2B576ms.png> <https://lh6.googleusercontent.com/-WK_RIPk6KhI/VGGA_-O9z-I/AAAAAAAAAAc/CXMTVp26GHk/s1600/TCP%2Bconnect%2B275ms.png> <https://lh6.googleusercontent.com/-yJE4gR-dDAs/VGGBC2a5T1I/AAAAAAAAAAk/m3k_bcboS7E/s1600/response%2B284ms.png> -- You received this message because you are subscribed to the Google Groups "Firebug" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/firebug. To view this discussion on the web visit https://groups.google.com/d/msgid/firebug/7b984750-7170-441d-8c4b-9325da9f46eb%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
www.eperformancegroup.com.har
Description: Binary data
