Roman O. Vlasov added the comment:
Antoine, Martin, thank you for your replies. You was right: NT socket was not
in blocking mode (in 1st case). I didn't knew how to determine socket mode in
NT, so I explicitly set socket mode to blocking in _ssl.c before calling
SSL_do_handshake() for
Roman O. Vlasov added the comment:
To reproduce the 100% CPU load problem, we used a simple python TLS client on
separate linux PC with Traffic control utility (tc):
tc qdisc change dev eth0 root netem delay 5000ms
After in-depth analyzing, we realized that _ssl.c behaves differently