ColossalAI/colossalai/autochunk/estimate_memory.py

235 lines
9.1 KiB
Python

from typing import Dict, List
import torch
from torch.fx.node import Node
from .utils import NodeMgr, get_node_shape, is_non_memory_node
class EstimateMemory(object):
"""
Estimate memory with chunk
"""
def __init__(self) -> None:
pass
def _get_node_size(self, x: Node) -> float:
"""
return node size in MB
"""
x = x.meta["tensor_meta"]
if not hasattr(x, "numel"):
out = sum([i.numel * torch.tensor([], dtype=i.dtype).element_size() for i in x])
else:
out = x.numel * torch.tensor([], dtype=x.dtype).element_size()
out = float(out) / 1024**2
return out
def _add_active_node(self, n: Node, active_nodes: Dict, chunk_ratio: float) -> None:
"""
add an active node and its shape to active node dict
"""
if get_node_shape(n) is None:
return
if n.op == "placeholder":
return
if n not in active_nodes:
node_size = self._get_node_size(n) * chunk_ratio
active_nodes[n] = node_size
def _build_delete_node_dict(self, node_mgr: NodeMgr) -> Dict:
"""
build delete node dict, means node should be deleted at what time
"""
delete_node_dict = {}
for idx, node in enumerate(node_mgr.get_node_list()):
# skip non shape node
if get_node_shape(node) is None:
continue
# dont remove free nodes
elif node.op == "placeholder":
delete_node_dict[node] = len(node_mgr.get_node_list())
# node no user
elif len(node.users) == 0:
delete_node_dict[node] = idx
# log max use
else:
node_user_idx = [node_mgr.find_node_idx(i) for i in node.users.keys()]
delete_node_dict[node] = max(node_user_idx)
return delete_node_dict
def _remove_deactive_node(
self, user_idx: int, user: Node, active_nodes: List, delete_node_dict: List, kept_nodes: List = None
) -> None:
"""
remove deactivate nodes from active nodes
"""
if kept_nodes is None:
kept_nodes = []
if user.op in ("output",):
return
for node in list(active_nodes.keys()):
# dont delete kept nodes
if node in kept_nodes:
continue
# should be deleted
if delete_node_dict[node] <= user_idx:
active_nodes.pop(node)
def _get_tmp_memory(self, node, not_contiguous_list, delete=False):
mem = 0
not_contiguous_ops = ["permute"]
if node.op == "call_function" and any(n in node.name for n in ["matmul", "reshape"]):
for n in node.args:
if n in not_contiguous_list:
# matmul won't change origin tensor, but create a tmp copy
mem += self._get_node_size(n)
elif node.op == "call_module":
for n in node.args:
if n in not_contiguous_list:
# module will just make origin tensor to contiguous
if delete:
not_contiguous_list.remove(n)
elif node.op == "call_method" and any(i in node.name for i in not_contiguous_ops):
if node not in not_contiguous_list:
not_contiguous_list.append(node)
return mem
def _get_chunk_ratio(self, node, chunk_node_dim, chunk_size):
if node not in chunk_node_dim:
return 1.0
node_shape = get_node_shape(node)
chunk_dim = chunk_node_dim[node]["chunk_dim"]
if chunk_dim is None:
return 1.0
else:
return chunk_size / float(node_shape[chunk_dim])
def _print_compute_op_mem_log(self, log, nodes, title=None):
if title:
print(title)
for idx, (l, n) in enumerate(zip(log, nodes)):
if n.op in ["placeholder", "get_attr", "output"]:
continue
if any(i in n.name for i in ["getitem", "getattr"]):
continue
print("%s:%.2f \t" % (n.name, l), end="")
if (idx + 1) % 3 == 0:
print("")
print("\n")
def _add_active_nodes_from_list(self, active_nodes: List, nodes: List) -> List:
"""
add active nodes from nodes
"""
for n in nodes:
self._add_active_node(n, active_nodes, 1)
def _get_memory_from_active_nodes(self, active_nodes: Dict) -> float:
"""
sum all memory of active nodes
"""
out = [i for i in active_nodes.values()]
out = sum(out)
return out
def estimate_chunk_inference_mem(self, node_list: List, chunk_infos: Dict = None, print_mem: bool = False):
"""
Estimate inference memory with chunk
Args:
node_list (List): _description_
chunk_infos (Dict): Chunk information. Defaults to None.
print_mem (bool): Wether to print peak memory of every node. Defaults to False.
Returns:
act_memory_peak_log (List): peak memory of every node
act_memory_after_node_log (List): memory after executing every node
active_node_list_log (List): active nodes of every node. active nodes refer to
nodes generated but not deleted.
"""
act_memory = 0.0
act_memory_peak_log = []
act_memory_after_node_log = []
active_nodes = {}
active_nodes_log = []
not_contiguous_list = []
node_mgr = NodeMgr(node_list)
delete_node_dict = self._build_delete_node_dict(node_mgr)
use_chunk = True if chunk_infos is not None else False
chunk_within = False
chunk_region_idx = None
chunk_ratio = 1 # use it to estimate chunk mem
chunk_inputs_all = []
if use_chunk:
chunk_regions = [i["region"] for i in chunk_infos]
chunk_starts = [i[0] for i in chunk_regions]
chunk_ends = [i[1] for i in chunk_regions]
chunk_inputs = [i["inputs"] for i in chunk_infos]
chunk_inputs_non_chunk = [i["inputs_non_chunk"] for i in chunk_infos]
chunk_inputs_all = [j for i in chunk_inputs for j in i] + [j for i in chunk_inputs_non_chunk for j in i]
chunk_outputs = [i["outputs"] for i in chunk_infos]
chunk_node_dim = [i["node_chunk_dim"] for i in chunk_infos]
chunk_sizes = [i["chunk_size"] if "chunk_size" in i else 1 for i in chunk_infos]
for idx, node in enumerate(node_mgr.get_node_list()):
# if node in chunk start nodes, change chunk ratio and add chunk_tensor
if use_chunk and idx in chunk_starts:
chunk_within = True
chunk_region_idx = chunk_starts.index(idx)
self._add_active_nodes_from_list(active_nodes, chunk_outputs[chunk_region_idx])
# determine chunk ratio for current node
if chunk_within:
chunk_ratio = self._get_chunk_ratio(
node, chunk_node_dim[chunk_region_idx], chunk_sizes[chunk_region_idx]
)
# add current node as active node
self._add_active_node(node, active_nodes, chunk_ratio)
act_memory = self._get_memory_from_active_nodes(active_nodes)
# if node is placeholder, just add the size of the node
if node.op == "placeholder":
act_memory_peak_log.append(act_memory)
# skip output
elif node.op == "output":
continue
# no change for non compute node
elif is_non_memory_node(node):
act_memory_peak_log.append(act_memory)
# node is a compute op, calculate tmp
else:
# forward memory
# TODO: contiguous_memory still not accurate for matmul, view, reshape and transpose
tmp_memory = self._get_tmp_memory(node, not_contiguous_list, delete=True) * chunk_ratio
# record max act memory
act_memory_peak_log.append(act_memory + tmp_memory)
# remove_deactive_node
self._remove_deactive_node(idx, node, active_nodes, delete_node_dict, kept_nodes=chunk_inputs_all)
# if node in chunk end nodes, restore chunk settings
if use_chunk and idx in chunk_ends:
self._remove_deactive_node(idx, node, active_nodes, delete_node_dict) # dont provide kept nodes now
chunk_within = False
chunk_ratio = 1
chunk_region_idx = None
act_memory = self._get_memory_from_active_nodes(active_nodes)
act_memory_after_node_log.append(act_memory)
active_nodes_log.append(active_nodes.copy())
if print_mem:
print("with chunk" if use_chunk else "without chunk")
self._print_compute_op_mem_log(act_memory_peak_log, node_mgr.get_node_list(), "peak")
# param_memory = parameter_size(gm)
# all_memory = act_memory + param_memory
return act_memory_peak_log, act_memory_after_node_log, active_nodes_log