I’m testing a private instance of WPT and wanted to be sure that the agent is behaving in a way I can trust.
I had results that I do not understand :
The queries 5 to 10 (with the long orange bars) are all images and seems to wait more than 1s for the server. The first query to the server (request #5) has a long TTFB, so I guess it’s normal that the 5 other queries are waiting for it. However, the 5 other queries have a “Content Download” time of 0, is it a bug of the agent ?
The waiting time for the server was consistent from test to test, but because it’s a CDN it should not be that long, so I wanted to know if it’s a bug of the installed agent or really a problem coming from the CDN.
So I tested the same page from Dulles and Paris public locations and had very different results
From Paris :
Here the “initial connection” time of the requests 6 to 9 looks reasonable, but the TTFB is very long, actually as long as the “initial connection time” of the test made from my server (coincidence ?).
And the “content download” time is still to 0.
Seeing two locations telling me the CDN takes time to answer, but that the waiting time appears differently, I wanted a last test to know if I could trust the agent or not.
At last, I tested from Dulles, because I guess it’s an agent you trust, and the results are definitely not the same, actually they look normal :
The total time to get the resource is reasonable (300ms to have a small resource from the other side of the planet), the initial connection time of resources 5 to 9 seems to last as long as the TTFB of the resource 4 (due to HTTP keep-alive ?), but the download time is still 0.
Why do I have so much inconsistencies between 3 different agents ?
Can I blame the CDN or not ?