Because the strategy is to exhaust all live references, and then all references in referenced objects, this is known as a ''[[breadth-first]]'' list copying garbage collection scheme.
==Sample algorithm==
<pre>
initialize() =
tospace = N/2
fromspace = 0
allocPtr = fromspace
scanPtr = whatever -- only used during collection
</pre>
<pre>
allocate(n) =
If allocPtr + n > fromspace + N/2
collect()
EndIf
If allocPtr + n > fromspace + N/2
fail “insufficient memory”
EndIf
o = allocPtr
allocPtr = allocPtr + n
return o
</pre>
<pre>
collect() =
swap(fromspace, tospace)
allocPtr = fromspace
scanPtr = fromspace
-- scan every root you've got
ForEach root in the stack -- or elsewhere
root = copy(root)
EndForEach
-- scan objects in the to-space (including objects added by this loop)
While scanPtr < allocPtr
ForEach reference r from o (pointed to by scanPtr)
r = copy(r)
EndForEach
scanPtr = scanPtr + o.size() -- points to the next object in the to-space, if any
