# recv buffer
# - default: 208KB
# - max: 208KB
$ cat /proc/sys/net/core/rmem_max
212992
$ sysctl net.core.rmem_max
net.core.rmem_max = 212992
$ cat /proc/sys/net/core/rmem_default
212992
$ sysctl net.core.rmem_default
net.core.rmem_default = 212992
# send buffer
# - default: 208KB
# - max: 208KB
$ cat /proc/sys/net/core/wmem_max
212992
$ sysctl net.core.wmem_max
net.core.wmem_max = 212992
$ cat /proc/sys/net/core/wmem_default
212992
$ sysctl net.core.wmem_default
net.core.wmem_default = 212992
$ cat /proc/sys/net/ipv4/tcp_rmem
4096 131072 6291456
$ sysctl net.ipv4.tcp_rmem
net.ipv4.tcp_rmem = 4096 131072 6291456
$ cat /proc/sys/net/ipv4/tcp_wmem
4096 16384 4194304
$ sysctl net.ipv4.tcp_wmem
net.ipv4.tcp_rmem = 4096 16384 4194304
$ cat /proc/sys/net/ipv4/tcp_window_scaling
1
$ sysctl -w net.ipv4.tcp_window_scaling = 1