What is the default size of datagram queue length in Unix Domain Sockets (AF_UNIX)? Is it configurable?
The previous answers/comments failed to understand that the OP was talking about maximum queue length in datagrams (max_dram_qlen) and not in bytes. The OS provides settings for both sizes.
You can set max_dgram_qlen using the following command:
sysctl net.unix.max_dgram_qlen=128You may need to run with sudo and you may also need to put double quotes around max_dgram_qlen=128 depending on your shell.
Also, see What's the practical limit on the size of single packet transmitted over domain socket?.
man unix(7):
The SO_SNDBUF socket option does have an effect for UNIX domain sockets, but the SO_RCVBUF option does not. For datagram sockets, the SO_SNDBUF value imposes an upper limit on the size of outgoing datagrams. This limit is calculated as the doubled (see socket(7)) option value less 32 bytes used for overhead.