[CLI] refactored the launch CLI and fixed bugs in multi-node launching (#844)

* [cli] fixed multi-node job launching

* [cli] fixed a bug in version comparison

* [cli] support launching with env var

* [cli] fixed multi-node job launching

* [cli] fixed a bug in version comparison

* [cli] support launching with env var

* added docstring

* [cli] added extra launch arguments

* [cli] added default launch rdzv args

* [cli] fixed version comparison

* [cli] added docstring examples and requierment

* polish docstring

* polish code

* polish code

colossalai/cli/launcher/__init__.py

@@ -5,27 +5,34 @@ from colossalai.context import Config
 
 @click.command(help="Launch distributed training on a single node or multiple nodes",
                context_settings=dict(ignore_unknown_options=True))
-@click.option("-H", "-host", "--host", type=str, default=None, help="the list of machines to launch")
-@click.option("--hostfile",
+@click.option("-H",
+              "-host",
+              "--host",
               type=str,
               default=None,
-              help="Hostfile path that defines the device pool available to the job (e.g. worker-name:number of slots)")
+              help="the list of hostnames to launch in the format <host1>,<host2>")
 @click.option(
-    "--include",
+    "--hostfile",
     type=str,
     default=None,
-    help=
-    "Specify computing devices to use during execution. String format is NODE_SPEC@NODE_SPEC where NODE_SPEC=<worker-name>:<list-of-slots>"
-)
+    help="Hostfile path that defines the device pool available to the job, each line in the file is a hostname")
+@click.option("--include",
+              type=str,
+              default=None,
+              help="Specify computing devices to use during execution. String format is <host1>,<host2>,"
+              " only effective when used with --hostfile.")
 @click.option(
     "--exclude",
     type=str,
     default=None,
     help=
-    "Specify computing devices to NOT use during execution. Mutually exclusive with --include. Formatting is the same as --include."
-)
-@click.option("--num_nodes", type=int, default=-1, help="Total number of worker nodes to use.")
-@click.option("--nproc_per_node", type=int, default=-1, help="Number of GPUs to use on each node.")
+    "Specify computing devices to NOT use during execution. Mutually exclusive with --include. Formatting is the same as --includ,"
+    " only effective when used with --hostfile.")
+@click.option("--num_nodes",
+              type=int,
+              default=-1,
+              help="Total number of worker nodes to use, only effective when used with --hostfile.")
+@click.option("--nproc_per_node", type=int, default=None, help="Number of GPUs to use on each node.")
 @click.option("--master_port",
               type=int,
               default=29500,
@@ -35,34 +42,43 @@ from colossalai.context import Config
               default="127.0.0.1",
               help="(optional) IP address of node 0, will be inferred via 'hostname -I' if not specified.")
 @click.option(
-    "--launcher",
-    type=click.Choice(['torch', 'openmpi', 'slurm'], case_sensitive=False),
-    default="torch",
-    help="(optional) choose launcher backend for multi-node training. Options currently include PDSH, OpenMPI, SLURM.")
-@click.option("--launcher_args",
-              type=str,
-              default=None,
-              help="(optional) pass launcher specific arguments as a single quoted argument.")
+    "--extra_launch_args",
+    type=str,
+    default=None,
+    help=
+    "Set additional torch distributed launcher arguments such as --standalone. The format is --extra_launch_args arg1=1,arg2=2. "
+    "This will be converted to --arg1=1 --arg2=2 during execution")
+@click.option("--ssh-port", type=int, default=None, help="(optional) the port used for ssh connection")
 @click.argument("user_script", type=str)
 @click.argument('user_args', nargs=-1)
 def run(host: str, hostfile: str, num_nodes: int, nproc_per_node: int, include: str, exclude: str, master_addr: str,
-        master_port: int, launcher: str, launcher_args: str, user_script: str, user_args: str):
+        master_port: int, extra_launch_args: str, ssh_port: int, user_script: str, user_args: str) -> None:
     """
     To launch multiple processes on a single node or multiple nodes via command line.
 
     Usage::
-        # run on the current node with all available GPUs
-        colossalai run train.py
+        # run with 4 GPUs on the current node use default port 29500
+        colossalai run --nprocs_per_node 4 train.py
 
-        # run with only 2 GPUs on the current node
-        colossalai run --nprocs_per_node 2 train.py
+        # run with 2 GPUs on the current node at port 29550
+        colossalai run --nprocs_per_node 4 --master_port 29550 train.py
 
         # run on two nodes
-        colossalai run --host <host1>,<host2> train.py
+        colossalai run --host <host1>,<host2> --master_addr host1  --nprocs_per_node 4 train.py
 
         # run with hostfile
-        colossalai run --hostfile <file_path> train.py
+        colossalai run --hostfile <file_path> --master_addr <host>  --nprocs_per_node 4 train.py
+
+        # run with hostfile with only included hosts
+        colossalai run --hostfile <file_path> --master_addr host1 --include host1,host2  --nprocs_per_node 4 train.py
+
+        # run with hostfile excluding the hosts selected
+        colossalai run --hostfile <file_path> --master_addr host1 --exclude host2  --nprocs_per_node 4 train.py
     """
+    if not user_script.endswith('.py'):
+        click.echo(f'Error: invalid Python file {user_script}. Did you use a wrong option? Try colossalai run --help')
+        exit()
+
     args_dict = locals()
     args = Config(args_dict)
     args.user_args = list(args.user_args)