fs: copyfile: don't touch callback at all for <1G files

This again wastes a lot of time, as `set_size` might trigger
a pbar refresh.

Related #229
Related iterative/dvc#9914

Author: efiop

src/dvc_objects/fs/utils.py

@@ -142,48 +142,62 @@ def makedirs(path, exist_ok: bool = False, mode: Optional[int] = None) -> None:
         )
 
 
-def copyfile(
+def _copyfile_with_pbar(
     src: "AnyFSPath",
     dest: "AnyFSPath",
+    total: int,
     callback: Optional["Callback"] = None,
     no_progress_bar: bool = False,
     name: Optional[str] = None,
+):
+    from .callbacks import Callback
+
+    name = name if name else os.path.basename(dest)
+
+    if callback:
+        callback.set_size(total)
+
+    with open(src, "rb") as fsrc, open(dest, "wb+") as fdest:
+        with Callback.as_tqdm_callback(
+            callback,
+            size=total,
+            bytes=True,
+            disable=no_progress_bar,
+            desc=name,
+        ) as cb:
+            wrapped = cb.wrap_attr(fdest, "write")
+            while True:
+                buf = fsrc.read(LOCAL_CHUNK_SIZE)
+                if not buf:
+                    break
+                wrapped.write(buf)
+
+    if callback:
+        callback.absolute_update(total)
+
+
+def copyfile(
+    src: "AnyFSPath",
+    dest: "AnyFSPath",
+    **kwargs,
 ) -> None:
     """Copy file with progress bar"""
-    name = name if name else os.path.basename(dest)
     total = os.stat(src).st_size
 
     if os.path.isdir(dest):
         dest = os.path.join(dest, os.path.basename(src))
 
-    if callback:
-        callback.set_size(total)
-
     try:
         system.reflink(src, dest)
+        return
     except OSError:
-        if total < COPY_PBAR_MIN_SIZE:
-            shutil.copyfile(src, dest)
-        else:
-            from .callbacks import Callback
-
-            with open(src, "rb") as fsrc, open(dest, "wb+") as fdest:
-                with Callback.as_tqdm_callback(
-                    callback,
-                    size=total,
-                    bytes=True,
-                    disable=no_progress_bar,
-                    desc=name,
-                ) as cb:
-                    wrapped = cb.wrap_attr(fdest, "write")
-                    while True:
-                        buf = fsrc.read(LOCAL_CHUNK_SIZE)
-                        if not buf:
-                            break
-                        wrapped.write(buf)
+        pass
 
-    if callback:
-        callback.absolute_update(total)
+    if total < COPY_PBAR_MIN_SIZE:
+        shutil.copyfile(src, dest)
+        return
+
+    _copyfile_with_pbar(src, dest, total, **kwargs)
 
 
 def tmp_fname(fname: "AnyFSPath" = "") -> "AnyFSPath":