transport_base: Poll timeout or error, errno=Connection already in progress

[axellin]

Hi,
When I testing the esp32-cam, I found it's easy to hit below warning
W (31345) transport_base: Poll timeout or error, errno=Connection already in progress, fd=55, timeout_ms=5000
when upload a 40 ~ 100kb jpeg file to http server.
(It's actually not just a warning, the upload failed)
Increase the timeout_ms does not help.

Any idea how to address this issue?

In additional, the upload is slow, it takes about 30 seconds to uplaod a 60KB file.
Is this normal?

Test with esp-idf-v5.1 and v5.2.

[axellin]

I found below debug log:
D (32596) transport_base: poll_write: select - Timeout before any socket was ready!
W (32596) transport_base: tcp Poll timeout or error, errno=Connection already in progress, fd=55, timeout_ms=10000

So sometimes, it takes much longer time to write. ( from a few seconds to more than 20 seconds)
Is it safe setting timeout_ms = -1 in esp_http_client_config_t?