Look into increasing TCP backlock on listening socket
bmenrigh opened this issue · comments
Go doesn't seem to provide a way to control the TCP backlog setting on a socket but if we create the socket with syscalls we should be able to.
From listen man page:
The backlog argument defines the maximum length to which the queue of pending connections for sockfd may grow. If a connection request arrives when the queue is full, the client may receive an
error with an indication of ECONNREFUSED or, if the underlying protocol supports retransmission, the request may be ignored so that a later reattempt at connection succeeds.
The behavior of the backlog argument on TCP sockets changed with Linux 2.2. Now it specifies the queue length for completely established sockets waiting to be accepted, instead of the number of
incomplete connection requests. The maximum length of the queue for incomplete sockets can be set using /proc/sys/net/ipv4/tcp_max_syn_backlog. When syncookies are enabled there is no logical
maximum length and this setting is ignored. See tcp(7) for more information.
If the backlog argument is greater than the value in /proc/sys/net/core/somaxconn, then it is silently truncated to that value; the default value in this file is 128. In kernels before 2.4.25,
this limit was a hard coded value, SOMAXCONN, with the value 128.