Explicit concurrent copying gc freed

The message “explicit concurrent copying gc freed” is related to garbage collection (gc) in a programming language/environment. It generally indicates that certain memory blocks were freed during the process of garbage collection using explicit concurrent copying algorithm.

Garbage collection is a process in programming languages where the memory used by objects that are no longer needed is automatically reclaimed. This helps in preventing memory leaks and improving memory management.

Explicit concurrent copying is a specific garbage collection algorithm that uses a technique called copy copying. In this algorithm, the memory is divided into two equal halves – one half is used for allocation and the other half is used for garbage collection. When the allocation half is full, the live objects are copied to the garbage collection half, and then the roles are reversed for the next garbage collection cycle.

During the process of explicit concurrent copying garbage collection, if a message like “explicit concurrent copying gc freed” appears, it means that some memory blocks were identified as garbage and were freed. These freed memory blocks were previously used by objects that are no longer in use or are unreachable from the program.

Here’s a simple example to illustrate this:

      
        // Create an array of objects
        var objects = [];
        for (var i = 0; i < 1000; i++) {
          objects.push({ id: i });
        }

        // Nullify the objects array
        objects = null;
      
    

In this example, an array of 1000 objects is created. However, after nullifying the "objects" array, these objects are no longer reachable from the program. Therefore, during the next garbage collection cycle, the explicit concurrent copying garbage collector will identify these unreachable objects and free the memory occupied by them.

The message "explicit concurrent copying gc freed" is just an indication that memory blocks were freed. It's not an error or warning message, but rather an informative one to let you know about the garbage collection process.