feat(mgb/compnode): expose mem_status and try_coalesce_all_free_memory to python

GitOrigin-RevId: 0ec2d556b10acb5efa602daded6a5f407cf686d9

python_module/megengine/_internal/__init__.py

@@ -654,3 +654,14 @@ def to_mgb_supported_dtype(dtype_):
     ):
         return dtype_
     return _detail._to_mgb_supported_dtype(dtype_)
+
+
+def return_free_memory():
+    """return free memory chunks on all devices.
+
+    This function will try it best to free all consecutive free chunks back to 
+    operating system, small pieces may not be returned.
+
+    Please notice that this function will not move any memory in-use.
+    """
+    _detail.CompNode._try_coalesce_all_free_memory()

python_module/src/swig/comp_node.i

@@ -49,6 +49,10 @@ class CompNode {
                     str2device_type(type, false));
             }
 
+            static void _try_coalesce_all_free_memory() {
+                CompNode::try_coalesce_all_free_memory();
+            }
+
             bool _check_eq(const CompNode &rhs) const {
                 return (*$self) == rhs;
             }
@@ -83,6 +87,10 @@ class CompNode {
             size_t __hash__() {
                 return mgb::hash(*$self);
             }
+
+            std::pair<size_t, size_t> _get_mem_status_bytes() {
+                return $self->get_mem_status_bytes();
+            }
         }
 
         %pythoncode {
@@ -121,6 +129,16 @@ class CompNode {
                 """physical locator: a tuple containing (type, device, stream)"""
                 t, d, s = self._get_locator()[3:]
                 return self.DEVICE_TYPE_MAP[t], d, s
+
+            @property
+            def mem_status_bytes(self) -> [int, int]:
+                """get (total, free) memory on the computing device in bytes.
+
+                Free memory includes memory chunks that buffered by the memory manager.
+
+                Please note that the results are the same for different CompNode within same device.
+                """
+                return self._get_mem_status_bytes()
         }
 };
 %template(_VectorCompNode) std::vector<CompNode>;

python_module/src/swig/mgb.i

@@ -30,6 +30,7 @@ void _init_bfloat16_types(PyObject *m); // implemented in bfloat16.cpp
 %template(_VectorInt) std::vector<int>;
 %template(_VectorString) std::vector<std::string>;
 %template(_PairStringSizeT) std::pair<std::string, size_t>;
+%template(_PairSizeTSizeT) std::pair<size_t, size_t>;
 %template(_VectorPairUint64String) std::vector<std::pair<uint64_t, std::string>>;
 
 %pythoncode %{