Interprocess Synchronization in Sheerpower

Overview

Sheerpower offers a robust interprocess synchronization feature that allows multiple processes to coordinate by sharing global variables. This synchronization is achieved through several key commands:

1. Set System Global: This statement allows a process to store a string value in a shared global variable. The value persists as long as at least one Sheerpower program is running.
   myid$ = uuid$ set system, global 'work_id': value uuid$
2. Ask System Global: This statement retrieves the value stored in a shared global variable.
   ask system, global 'work_id': value this_work_id$ print 'ID is: '; this_work_id$
3. Atomic Increments: This allows each process to request an incremented value, which can be used to establish process roles. The first process gets "1", others receive their unique incremented values.
   ask system, global 'synch_counter': increment, value my_counter$ if (my_counter$ = '1') then print 'I am the first' end if
4. Global Cache Performance and Lifetime: Globals are very efficient. They can be read and written at over ten million times per second. The global cache is deleted when the last Sheerpower program stops running, ensuring data persists only while it's needed.

Five Potential Uses

1. Master-Slave Process Coordination: The first process receiving the value "1" becomes the master, while others (slaves) handle tasks in parallel, knowing their role based on the incremented value.
2. Load Balancing Between Processes: Processes can track and share load balancing data, distributing tasks based on current loads.
3. Inter-process Messaging System: Processes can use the global cache as a message-passing system, sharing status updates or task completions.
4. Shared Configuration Settings: Processes can store and read global configuration settings, ensuring consistent behavior across multiple processes.
5. Distributed Data Aggregation: Multiple processes gather data and store results in global variables for real-time aggregation and reporting.

Conclusion

The interprocess synchronization feature in Sheerpower simplifies communication between processes, providing a way to coordinate tasks and share data in real time. Whether managing parallel processes, balancing loads, or aggregating data, this feature helps ensure that processes can efficiently work together without needing complex external systems.