1024 Words: SEND Buffers and Concurrent Connections

#devops #webperf #ado The relationship between SEND buffers and concurrent connections

The send buffer setting is the maximum amount of data a system will send before receiving an acknowledgement, and the receive window setting is the maximum size window the system will advertise.

Many folks tweak the send buffer settings on web and application servers as well as intermediate devices (proxies, load balancers, etc...) to optimize for high-speed, high-latency pipes. However, as this is often a system-wide configuration change, mucking with the SEND buffer sizes can directly impact the connection capacity of the system. Remember, "buffering" takes up memory, and so do connections (session and state table storage),