How to use the command "distccd" (with examples)

The “distccd” command is a server daemon for the distcc distributed compiler. It allows compilation jobs to be distributed across multiple networked machines, resulting in faster build times for large projects. By offloading the compilation process to remote servers, “distccd” helps optimize the use of computing resources and reduces the burden on a single machine.

Use case 1: Start a daemon with the default settings

Code:

distccd --daemon

Motivation: By starting a “distccd” daemon with the default settings, you can quickly set up a distributed compilation environment without any extra configurations. This is useful when you want to leverage the power of multiple machines for faster compilation without the need for customization.

Explanation: The “–daemon” option starts “distccd” as a daemon process, running in the background. This allows the server to accept compilation requests and distribute them to other machines in the network.

Example output:

distccd[1234] starting with version x.x.x
Listening on :::3632
Listening on 0.0.0.0:3632

Use case 2: Start a daemon, accepting connections from IPv4 private network ranges

Code:

distccd --daemon --allow-private

Motivation: In some cases, you might want to restrict the connections to your “distccd” server only from IPv4 private network ranges. This can help ensure that your distributed compilation resources are utilized only by trusted machines within your network.

Explanation: The “–allow-private” option configures the “distccd” server to accept connections only from IPv4 private network ranges. This restricts access to the server, ensuring that only authorized machines can participate in the distributed compilation process.

Example output:

distccd[1234] starting with version x.x.x
Allowing connections only from IPv4 private network ranges
Listening on :::3632
Listening on 0.0.0.0:3632

Use case 3: Start a daemon, accepting connections from a specific network address or address range

Code:

distccd --daemon --allow ip_address|network_prefix

Motivation: You may have specific machines or subnets that you want to allow access to your “distccd” server. By using the “–allow” option with a specific IP address or network range, you can control which machines can participate in the distributed compilation process.

Explanation: The “–allow” option specifies the network address or address range that is allowed to connect to the “distccd” server. You can either provide a single IP address or use CIDR notation to specify a network prefix.

Example output:

distccd[1234] starting with version x.x.x
Allowing connections only from 192.168.0.10/24
Listening on :::3632
Listening on 0.0.0.0:3632

Use case 4: Start a daemon with a lowered priority that can run a maximum of 4 tasks at a time

Code:

distccd --daemon --jobs 4 --nice 5

Motivation: By configuring “distccd” with a lower priority and limiting the number of concurrent compilation tasks, you can ensure that the distributed compilation process does not overly burden the resources of the server. This can be useful when you want to keep the server responsive to other tasks while still benefiting from distributed compilation.

Explanation: The “–jobs” option limits the maximum number of concurrent compilation tasks that can be handled by the “distccd” server. In this example, we set it to 4. The “–nice” option sets the server’s process priority to a lower value (higher priority) to prevent it from monopolizing resources.

Example output:

distccd[1234] starting with version x.x.x
Running with maximum 4 jobs
Nice value set to 5
Listening on :::3632
Listening on 0.0.0.0:3632

Use case 5: Start a daemon and register it via mDNS/DNS-SD (Zeroconf)

Code:

distccd --daemon --zeroconf

Motivation: Registering the “distccd” daemon via mDNS/DNS-SD (Zeroconf) makes it easier for clients to discover and connect to the server. This eliminates the need to manually configure the client machines with the server’s IP address.

Explanation: The “–zeroconf” option enables mDNS/DNS-SD (Zeroconf) registration for the “distccd” server. This allows clients on the network to discover the server using its service name without requiring explicit IP address configuration.

Example output:

distccd[1234] starting with version x.x.x
Registering via mDNS/DNS-SD (Zeroconf)
Listening on :::3632
Listening on 0.0.0.0:3632

Conclusion:

The “distccd” command provides a convenient way to set up and manage a distributed compilation environment. By utilizing the different options and settings available, you can customize the behavior of the “distccd” server to meet your specific requirements. Whether you want to restrict access, limit resource usage, or simplify client discovery, “distccd” offers the flexibility needed for efficient distributed compilation.