Super-server

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A super-server or sometimes called a service dispatcher is a type of daemon run generally on Unix-like systems.

[edit] Usage

It starts other servers when needed, normally with access to them checked by 'tcpd'. It uses no (or very little) resources when in idle state. This can be ideal for workstations used for local web development, client/server development or low traffic daemons with occasional usage such as ident and SSH.

[edit] Performance

There is a slight delay in connecting, thus when compared to pre-spawn servers, a 'super-server' setup may not be all that quick in reaction to connection attempts, especially when under high load. Some servers, such as hpa-tftpd, therefore takeover the socket and listen on it themselves for some specified interval, anticipating more connections to come.

[edit] Implementations

• inetd
• launchd
• ucspi-tcp
• xinetd