The default send window size in bytes. Refer to the following discussion of per-route metrics for setting a different value on a per route basis. See tcp_max_buf also.
49,152
4096 to 1,073,741,824
Yes
Note that this is the default value. An application can use setsockopt(3XNET) SO_SNDBUF to change the individual connection's send buffer.
Unstable