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Re: Large POST requests get stuck when sent with HTTP/2 (works with HTTP 1.1)

From: Daniel Stenberg via curl-library <>
Date: Fri, 19 Apr 2019 17:19:29 +0200 (CEST)

On Thu, 18 Apr 2019, Dmitri Trembovetski via curl-library wrote:

> I've compiled libcurl with HTTP/2 support (openssl, nghttp2) for my project.
> curl 7.56.1 (although I had the same issue with the latest, I backed out to
> that one due to unrelated issue with gzip encoding in the latest)

I would strongly urge you to not spend a lot of time debugging HTTP/2 on that
old release. We've fixed several HTTP/2 issues since then so you risk ending
up chasing things or seeing symptoms that aren't present in the current code.

Can you write up a smallish example code that reproduces the problem? If I
could point such a thing on my own test server I could take a look at it from
my side. HTTP/2 debugging can be a bit complicated.

> With app level logging I can see that CURLOPT_READFUNCTION callback gets
> invoked up until the point where another GET request happens, and then I see
> no callbacks anymore, and the connection eventually times out or is closed
> by the server.

This symptom matches a previous bug we had (and fixed) in curl's HTTP/2 code.

Received on 2019-04-19