recv_buf_size and send_buf_size tips

Question:  I have seen your great notes on Oracle network tuning and I saw this note on recv_buf_size and send_buf_size in the sqlnet.ora file:

"Starting in Oracle10g, if you are tuning your network to maximize throughput (as opposed to tuning for fast response time), Oracle suggests setting recv_buf_size and send_buf_size sqlnet.ora parameters equal to 3 times the Bandwidth Delay Product (BDP)."

How do I set the optimal values for the send_buf_size and recv_buf_size?

Answer:  As the name implies, the recv_buf_size and send_buf_size parameters in the sqlnet.ora file determine the size (in bytes) of the socket receive and send buffers for a SQL*Net connection.

The Oracle documentation suggests an arbitrarily high values for your send_buf_size and recv_buf_size, large enough to accommodate the largest possible packet size, not not too large. 

The optimal setting for send_buf_size and recv_buf_size is a tradeoff between slow network transmission (multiple packets required) vs. wasting RAM resources.

To prevent network contention, the values for recv_buf_size and send_buf_size should be set to the maximum amount of data that might be sent, at least 3x the value of your bandwidth delay product (BDP).  See these notes on computing your BDP value.

Remember, RAM is cheap, and a large Oracle*Net transmission and receive RAM buffer size can prevent network wait outages.

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