On Wed, 17 Dec 2008, Nikolas Coukouma wrote:

> We've been encountering some strange stall behavior, where (lib)curl seems
> to simply stop sending data. The errors are reproducible, but sporadic.
> We're happy to try debugging suggestions as well as possible solutions.

Can any (other) client PUT to that server?

> http://nikolasco.s3.amazonaws.com/broken_s3.zip

I'm looking at the 7.19.2-excerpt pcap and I think the TCP flow looks very
strange. Starting at frame #1803 there are several hundred duplicated TCP
acks!

Then at #4484 the client side seems to have stopped sending and the server
just keeps sending TCP acks for a very long time (200+) before both sides go
quite and then after 20 seconds idle time the server sends something.

If libcurl would be wrong here, why would the 400 response get read fine all
of a sudden? (the strace seems to imply that libcurl is waiting for receiving
data during that time) Is the server somehow waiting for or expecting
something else in the PUT request that you don't send?

-- 
  / daniel.haxx.se