UPDATE: i did a mistake. Uart settings of my esp was 1Mbit/s 8n1 with RTS enabled (instead of NO hw flow control) and my pc app had uart settings without hw flow control. With this configuration, I saw with oscilloscope that RTS signal from esp had positive pulses, and when esp lost bytes, pulse was...

MY SETUP I have my pc application using esp8266 with help of usb-uart converter and another pc app running as TCP server. Esp is connected to a WiFi network and it is configured with 1Mbit/s baudrate. I'm running a stress test in order to measure the maximum throughput for our next connected device....