How long does it take to preview a picture when it is generated?

Question

symfony

I ran into the following problem on my VPS:
I use the LiipImageBundle library to generate thumbnails for pictures, which is nothing more than a wrapper over gd.
When generating a preview for the first time, a very strange picture is obtained, as in the screenshot:

In fact, the picture is given in 400-600ms (with the status 201 Created ), and the rest of the time the connection just hangs, and resp. It turns out the total time to receive the file is 1 minute. Then if you request this picture, then everything is ok.
What could be the problem and where should I dig?
Now I have Nginx as a front-end server in front of apache, but I turned on redirects for any files on this domain to the backend, which had no effect.
UPD:The problem is in the status 201, if you manually set the status 200 in the code that generates the picture, then everything works out quickly!

Answer 1

The issue was resolved by updating nginx to the latest version, which began to give Content-Length for responses with 201 status.