Time delay Issue with async_write_some and async_read_some

From: Daggumati, Rajesh (rajesh.daggumati_at_[hidden])
Date: 2022-04-07 11:29:00

Hi Team,

We can see two different behaviours in communication when we tested in windows and Linux with same hardware .Windows responded slowly compared to Linux.
We are using  async_write_some  and async_read_some  methods from boost library for RS-232 communication with hardware(COM1).

m_serialPort.async_write_some(boost::asio::buffer(toSend),
            boost::bind(&SerialPortAsync::HandleSentData, this,
                        boost::asio::placeholders::error,
                        boost::asio::placeholders::bytes_transferred));

m_serialPort.async_read_some(boost::asio::buffer(m_RecvBuffer),
            boost::bind(&SerialPortAsync::HandleReceive, this,
            boost::asio::placeholders::error,
            boost::asio::placeholders::bytes_transferred));

Comparison   Linux Vs Windows for same application :

Linux
Sending     Time   --->    2020/11/23 17:34:56.678585,1064,   , <-- (+0.000151) (11)[010B0557,0D0001E8,03C40F] [tx-queue:24]   Send
Receiving   Time  --->     2020/11/23 17:34:56.680490,1064,   , --> (+0.001905) (8)[060B0557,040D00E8] [tx-queue:24]

Turnaround time : 0.001905

Windows
Sending     Time --->    2022/03/28 14:41:28.662338,5388,   , <-- (+0.000000) (11)[010B0457,0D0001E8,035BDA] [tx-queue:40]
Receiving   Time -->   2022/03/28 14:41:28.693591,5388,   , --> (+0.031253) (9)[06090457,0D0001B0,1F] [tx-queue:40]

Turnaround time : 0.031253

We want to know why windows takes more time as compared to Linux. We cannot put more debug logs in the application code. Below this layer, boost library play the role to transfer the data to the Serial port

Regards,
Rajesh D
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