Hello, I faced strange latencies during execution HTTP requests to a Java (Spring Web) application which is deployed on Google AppEngine Standard.
For testing purposes, I've used - VM in GCP and located in *us-central1* region to make client requests - Java Web App in Google AppEngine Standard and deployed in *us-east1* region Made exactly the same GET request to my application multiple times from VM in GCP. Below you can see a couple of request details *Attempt #1* *curl output* time_namelookup: 0.004209 time_connect: 0.005623 time_appconnect: 0.01674 time_pretransfer: 0.016828 time_starttransfer: 0.246101 size_request: 280 -------- time_total: 0.24617 *Google AppEngine Wallclock time* Total clock time in milliseconds spent by App Engine on the request. This time duration does not include time spent between the client and the server running the instance of your application (According to https://cloud.google.com/appengine/docs/standard/java/logs) 37ms So I expect that latency on Google network can be calculated as time_starttransfer - time_appconnect - warclock_time Try to explan this formula: we subtract time to connect to Google Frontend Server and time of processing requst by GAE infrastructure from time to receive the first byte of a response And we can see that we lost 192.361ms in Google Network *Attempt #2* *curl output* time_namelookup: 0.012408 time_connect: 0.014181 time_appconnect: 0.024485 time_pretransfer: 0.024586 time_starttransfer: 0.107834 size_request: 280 -------- time_total: 0.107901 *Google AppEngine Wallclock time* Total clock time in milliseconds spent by App Engine on the request. This time duration does not include time spent between the client and the server running the instance of your application (According to https://cloud.google.com/appengine/docs/standard/java/logs) 46ms Now we lost only 37.349ms in Google Network The difference between ~192ms and ~37ms makes me confused a bit. Could you please help me to understand this issue and may be suggest what I can do with it to make this latency low? -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to google-appengine+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/90da98b2-929b-4a58-ab44-8f937e473a8dn%40googlegroups.com.
