sonewconn: pcb 0xfffff8146e496a50: Listen queue overflow

sysctl kern.ipc.soacceptqueue=1024

# somaxconn is the OS buffer, backlog queue depth for accepting new incoming TCP
# connections. An application will have its own, separate max queue length
# (maxqlen) which can be checked with "netstat -Lan". The default is 128
# connections per application thread. Lets say your Nginx web server normally
# receives 100 connections/sec and is single threaded application. If clients
# are bursting in at a total of 250 connections/sec you may want to set the
# somaxconn at 512 to be a 512 deep connection buffer so the extra 122 clients
# (250-128=122) do not get denied service since you would have 412
# (512-100=412) extra queue slots. Also, a large listen queue will do a better
# job of avoiding Denial of Service (DoS) attacks if, and only if, your
# application can handle the TCP load at the cost of more RAM and CPU time.
# Nginx sets is backlog queue to the same as the OS somaxconn by default.
# Note: "kern.ipc.somaxconn" is not shown in "sysctl -a" output, but searching
# for "kern.ipc.soacceptqueue" gives the same value and both directives stand
# for the same buffer value.
#kern.ipc.soacceptqueue=1024  # (default 128 ; same as kern.ipc.somaxconn)