dvcfs: optimize get() by reducing index.info calls()

dvc/dependency/repo.py

@@ -98,12 +98,13 @@ def download(self, to: "Output", jobs: Optional[int] = None):
 
         files = super().download(to=to, jobs=jobs)
         if not isinstance(to.fs, LocalFileSystem):
-            return files
+            return
 
         hashes: list[tuple[str, HashInfo, dict[str, Any]]] = []
-        for src_path, dest_path in files:
+        for src_path, dest_path, *rest in files:
             try:
-                hash_info = self.fs.info(src_path)["dvc_info"]["entry"].hash_info
+                info = rest[0] if rest else self.fs.info(src_path)
+                hash_info = info["dvc_info"]["entry"].hash_info
                 dest_info = to.fs.info(dest_path)
             except (KeyError, AttributeError):
                 # If no hash info found, just keep going and output will be hashed later
@@ -112,7 +113,6 @@ def download(self, to: "Output", jobs: Optional[int] = None):
                 hashes.append((dest_path, hash_info, dest_info))
         cache = to.cache if to.use_cache else to.local_cache
         cache.state.save_many(hashes, to.fs)
-        return files
 
     def update(self, rev: Optional[str] = None):
         if rev:

dvc/fs/__init__.py

@@ -1,5 +1,5 @@
 import glob
-from typing import Optional
+from typing import Optional, Union
 from urllib.parse import urlparse
 
 from dvc.config import ConfigError as RepoConfigError
@@ -47,12 +47,24 @@
 
 def download(
     fs: "FileSystem", fs_path: str, to: str, jobs: Optional[int] = None
-) -> list[tuple[str, str]]:
+) -> list[Union[tuple[str, str], tuple[str, str, dict]]]:
     from dvc.scm import lfs_prefetch
 
     from .callbacks import TqdmCallback
 
     with TqdmCallback(desc=f"Downloading {fs.name(fs_path)}", unit="files") as cb:
+        if isinstance(fs, DVCFileSystem):
+            lfs_prefetch(
+                fs,
+                [
+                    f"{fs.normpath(glob.escape(fs_path))}/**"
+                    if fs.isdir(fs_path)
+                    else glob.escape(fs_path)
+                ],
+            )
+            if not glob.has_magic(fs_path):
+                return fs._get(fs_path, to, batch_size=jobs, callback=cb)
+
         # NOTE: We use dvc-objects generic.copy over fs.get since it makes file
         # download atomic and avoids fsspec glob/regex path expansion.
         if fs.isdir(fs_path):
@@ -69,15 +81,6 @@ def download(
             from_infos = [fs_path]
             to_infos = [to]
 
-        if isinstance(fs, DVCFileSystem):
-            lfs_prefetch(
-                fs,
-                [
-                    f"{fs.normpath(glob.escape(fs_path))}/**"
-                    if fs.isdir(fs_path)
-                    else glob.escape(fs_path)
-                ],
-            )
         cb.set_size(len(from_infos))
         jobs = jobs or fs.jobs
         generic.copy(fs, from_infos, localfs, to_infos, callback=cb, batch_size=jobs)

dvc/fs/dvc.py

@@ -6,20 +6,24 @@
 import threading
 from collections import deque
 from contextlib import ExitStack, suppress
+from glob import has_magic
 from typing import TYPE_CHECKING, Any, Callable, Optional, Union
 
-from fsspec.spec import AbstractFileSystem
+from fsspec.spec import DEFAULT_CALLBACK, AbstractFileSystem
 from funcy import wrap_with
 
 from dvc.log import logger
-from dvc_objects.fs.base import FileSystem
+from dvc.utils.threadpool import ThreadPoolExecutor
+from dvc_objects.fs.base import AnyFSPath, FileSystem
 
 from .data import DataFileSystem
 
 if TYPE_CHECKING:
     from dvc.repo import Repo
     from dvc.types import DictStrAny, StrPath
 
+    from .callbacks import Callback
+
 logger = logger.getChild(__name__)
 
 RepoFactory = Union[Callable[..., "Repo"], type["Repo"]]
@@ -474,9 +478,110 @@ def _info(  # noqa: C901
         info["name"] = path
         return info
 
+    def get(
+        self,
+        rpath,
+        lpath,
+        recursive=False,
+        callback=DEFAULT_CALLBACK,
+        maxdepth=None,
+        batch_size=None,
+        **kwargs,
+    ):
+        self._get(
+            rpath,
+            lpath,
+            recursive=recursive,
+            callback=callback,
+            maxdepth=maxdepth,
+            batch_size=batch_size,
+            **kwargs,
+        )
+
+    def _get(  # noqa: C901
+        self,
+        rpath,
+        lpath,
+        recursive=False,
+        callback=DEFAULT_CALLBACK,
+        maxdepth=None,
+        batch_size=None,
+        **kwargs,
+    ) -> list[Union[tuple[str, str], tuple[str, str, dict]]]:
+        if (
+            isinstance(rpath, list)
+            or isinstance(lpath, list)
+            or has_magic(rpath)
+            or not self.exists(rpath)
+            or not recursive
+        ):
+            super().get(
+                rpath,
+                lpath,
+                recursive=recursive,
+                callback=callback,
+                maxdepth=maxdepth,
+                **kwargs,
+            )
+            return []
+
+        if os.path.isdir(lpath) or lpath.endswith(os.path.sep):
+            lpath = self.join(lpath, os.path.basename(rpath))
+
+        if self.isfile(rpath):
+            with callback.branched(rpath, lpath) as child:
+                self.get_file(rpath, lpath, callback=child, **kwargs)
+                return [(rpath, lpath)]
+
+        _files = []
+        _dirs: list[str] = []
+        for root, dirs, files in self.walk(rpath, maxdepth=maxdepth, detail=True):
+            if files:
+                callback.set_size((callback.size or 0) + len(files))
+
+            parts = self.relparts(root, rpath)
+            if parts in ((os.curdir,), ("",)):
+                parts = ()
+            dest_root = os.path.join(lpath, *parts)
+            if not maxdepth or len(parts) < maxdepth - 1:
+                _dirs.extend(f"{dest_root}{os.path.sep}{d}" for d in dirs)
+
+            key = self._get_key_from_relative(root)
+            _, dvc_fs, _ = self._get_subrepo_info(key)
+
+            for name, info in files.items():
+                src_path = f"{root}{self.sep}{name}"
+                dest_path = f"{dest_root}{os.path.sep}{name}"
+                _files.append((dvc_fs, src_path, dest_path, info))
+
+        os.makedirs(lpath, exist_ok=True)
+        for d in _dirs:
+            os.mkdir(d)
+
+        def _get_file(arg):
+            dvc_fs, src, dest, info = arg
+            dvc_info = info.get("dvc_info")
+            if dvc_info and dvc_fs:
+                dvc_path = dvc_info["name"]
+                dvc_fs.get_file(
+                    dvc_path, dest, callback=callback, info=dvc_info, **kwargs
+                )
+            else:
+                self.get_file(src, dest, callback=callback, **kwargs)
+            return src, dest, info
+
+        with ThreadPoolExecutor(max_workers=batch_size) as executor:
+            return list(executor.imap_unordered(_get_file, _files))
+
     def get_file(self, rpath, lpath, **kwargs):
         key = self._get_key_from_relative(rpath)
         fs_path = self._from_key(key)
+
+        dirpath = os.path.dirname(lpath)
+        if dirpath:
+            # makedirs raises error if the string is empty
+            os.makedirs(dirpath, exist_ok=True)
+
         try:
             return self.repo.fs.get_file(fs_path, lpath, **kwargs)
         except FileNotFoundError:
@@ -553,6 +658,45 @@ def immutable(self):
     def getcwd(self):
         return self.fs.getcwd()
 
+    def _get(
+        self,
+        from_info: Union[AnyFSPath, list[AnyFSPath]],
+        to_info: Union[AnyFSPath, list[AnyFSPath]],
+        callback: "Callback" = DEFAULT_CALLBACK,
+        recursive: bool = False,
+        batch_size: Optional[int] = None,
+        **kwargs,
+    ) -> list[Union[tuple[str, str], tuple[str, str, dict]]]:
+        # FileSystem.get is non-recursive by default if arguments are lists
+        # otherwise, it's recursive.
+        recursive = not (isinstance(from_info, list) and isinstance(to_info, list))
+        return self.fs._get(
+            from_info,
+            to_info,
+            callback=callback,
+            recursive=recursive,
+            batch_size=batch_size,
+            **kwargs,
+        )
+
+    def get(
+        self,
+        from_info: Union[AnyFSPath, list[AnyFSPath]],
+        to_info: Union[AnyFSPath, list[AnyFSPath]],
+        callback: "Callback" = DEFAULT_CALLBACK,
+        recursive: bool = False,
+        batch_size: Optional[int] = None,
+        **kwargs,
+    ) -> None:
+        self._get(
+            from_info,
+            to_info,
+            callback=callback,
+            batch_size=batch_size,
+            recursive=recursive,
+            **kwargs,
+        )
+
     @property
     def fsid(self) -> str:
         return self.fs.fsid

tests/func/test_import.py

@@ -13,7 +13,7 @@
 from dvc.testing.tmp_dir import make_subrepo
 from dvc.utils.fs import remove
 from dvc_data.hashfile import hash
-from dvc_data.index.index import DataIndexDirError
+from dvc_data.index.index import DataIndex, DataIndexDirError
 
 
 def test_import(tmp_dir, scm, dvc, erepo_dir):
@@ -725,12 +725,41 @@ def test_import_invalid_configs(tmp_dir, scm, dvc, erepo_dir):
         )
 
 
-def test_import_no_hash(tmp_dir, scm, dvc, erepo_dir, mocker):
+@pytest.mark.parametrize(
+    "files,expected_info_calls",
+    [
+        ({"foo": "foo"}, {("foo",)}),
+        (
+            {
+                "dir": {
+                    "bar": "bar",
+                    "subdir": {"lorem": "ipsum", "nested": {"lorem": "lorem"}},
+                }
+            },
+            # info calls should be made for only directories
+            {("dir",), ("dir", "subdir"), ("dir", "subdir", "nested")},
+        ),
+    ],
+)
+def test_import_no_hash(
+    tmp_dir, scm, dvc, erepo_dir, mocker, files, expected_info_calls
+):
     with erepo_dir.chdir():
-        erepo_dir.dvc_gen("foo", "foo content", commit="create foo")
-
-    spy = mocker.spy(hash, "file_md5")
-    stage = dvc.imp(os.fspath(erepo_dir), "foo", "foo_imported")
-    assert spy.call_count == 1
-    for call in spy.call_args_list:
-        assert stage.outs[0].fs_path != call.args[0]
+        erepo_dir.dvc_gen(files, commit="create foo")
+
+    file_md5_spy = mocker.spy(hash, "file_md5")
+    index_info_spy = mocker.spy(DataIndex, "info")
+    name = next(iter(files))
+
+    dvc.imp(os.fspath(erepo_dir), name, "out")
+
+    local_hashes = [
+        call.args[0]
+        for call in file_md5_spy.call_args_list
+        if call.args[1].protocol == "local"
+    ]
+    # no files should be hashed, should use existing metadata
+    assert not local_hashes
+    assert {
+        call.args[1] for call in index_info_spy.call_args_list
+    } == expected_info_calls