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SQL*Net message to client 28819 0.00 0.06
SQL*Net message from client 28819 2.02 27.39
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The number of round trip calls between the client and server can be reduced by increasing the SDU and TDU parameters in listener.ora and tnsnames.ora files. By default TCP network sends 1500 bytes in one package. Set it to 8K.

In the TCP network, the network first receives data from a process, then it will wait for 20 ms to get additional data, so that it will combine the data and send to the client. The is called nagle algorithm. In general UNIX administrator will not disable the algorithm at the UNIX level. So, Oracle provided protocol.ora file to disable it.

Also, in protocol.ora file, set tcp.nodelay=yes. This setting may not be required for newer version of oracle (from 8.1.7.4 )

If you test your process with event 10046 level 12, you will see the real elapsed time under SQL*Net message. That time is reported in centiseconds. By closely reading the raw trace file, you will come to know that whether your client is sending more data, or server is sending data to client. With various values of SDU and TDU, you can arrive the best settings.

Tamil