diff --git a/borg/archive.py b/borg/archive.py
index 178ad94b8..0c57680f4 100644
--- a/borg/archive.py
+++ b/borg/archive.py
@@ -204,6 +204,7 @@ class Archive:
         if start is None:
             start = datetime.utcnow()
             start_monotonic = time.monotonic()
+        self.chunker_params = chunker_params
         self.start = start
         self.start_monotonic = start_monotonic
         if end is None:
@@ -227,7 +228,7 @@ class Archive:
                 raise self.DoesNotExist(name)
             info = self.manifest.archives[name]
             self.load(info[b'id'])
-            self.zeros = b'\0' * (1 << chunker_params[1])
+            self.zeros = None
 
     def _load_meta(self, id):
         data = self.key.decrypt(id, self.repository.get(id))
@@ -405,6 +406,8 @@ Number of files: {0.stats.nfiles}'''.format(
                 with backup_io():
                     os.link(source, path)
             else:
+                if sparse and self.zeros is None:
+                    self.zeros = b'\0' * (1 << self.chunker_params[1])
                 with backup_io():
                     fd = open(path, 'wb')
                 with fd:
diff --git a/docs/api.rst b/docs/api.rst
deleted file mode 100644
index f05cdbc29..000000000
--- a/docs/api.rst
+++ /dev/null
@@ -1,86 +0,0 @@
-
-.. IMPORTANT: this file is auto-generated by "setup.py build_api", do not edit!
-
-
-API Documentation
-=================
-
-.. automodule:: borg.archive
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.archiver
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.cache
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.chunker
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.compress
-    :members: get_compressor, Compressor, CompressorBase
-    :undoc-members:
-
-.. automodule:: borg.crypto
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.fuse
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.hashindex
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.helpers
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.key
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.keymanager
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.locking
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.logger
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.lrucache
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.platform
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.platform_linux
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.remote
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.repository
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.shellpattern
-    :members:
-    :undoc-members:
-
-.. automodule:: borg.xattr
-    :members:
-    :undoc-members:
diff --git a/docs/development.rst b/docs/development.rst
index afc1e21a9..7dc2941ac 100644
--- a/docs/development.rst
+++ b/docs/development.rst
@@ -183,20 +183,19 @@ Important notes:
 Regenerate usage files
 ----------------------
 
-Usage and API documentation is currently committed directly to git,
+Usage documentation is currently committed directly to git,
 although those files are generated automatically from the source
 tree.
 
-When a new module is added, the ``docs/api.rst`` file needs to be
-regenerated::
-
-  ./setup.py build_api
-
 When a command is added, a commandline flag changed, added or removed,
 the usage docs need to be rebuilt as well::
 
   ./setup.py build_usage
 
+However, we prefer to do this as part of our :ref:`releasing`
+preparations, so it is generally not necessary to update these when
+submitting patches that change something about the command line.
+
 Building the docs with Sphinx
 -----------------------------
 
@@ -270,7 +269,7 @@ Checklist:
 - update ``CHANGES.rst``, based on ``git log $PREVIOUS_RELEASE..``
 - check version number of upcoming release in ``CHANGES.rst``
 - verify that ``MANIFEST.in`` and ``setup.py`` are complete
-- ``python setup.py build_api ; python setup.py build_usage`` and commit
+- ``python setup.py build_usage`` and commit
 - tag the release::
 
     git tag -s -m "tagged/signed release X.Y.Z" X.Y.Z
diff --git a/docs/faq.rst b/docs/faq.rst
index 6c69d60b5..fbf213768 100644
--- a/docs/faq.rst
+++ b/docs/faq.rst
@@ -321,6 +321,13 @@ for a potential solution.
 
 Please note that this workaround only helps you for backup, not for restore.
 
+Can I backup my root partition (/) with Borg?
+---------------------------------------------
+
+Backing up your entire root partition works just fine, but remember to
+exclude directories that make no sense to backup, such as /dev, /proc,
+/sys, /tmp and /run.
+
 If it crashes with a UnicodeError, what can I do?
 -------------------------------------------------
 
diff --git a/setup.py b/setup.py
index e3b8beb9e..8f65963d5 100644
--- a/setup.py
+++ b/setup.py
@@ -213,43 +213,8 @@ class build_usage(Command):
         return is_subcommand
 
 
-class build_api(Command):
-    description = "generate a basic api.rst file based on the modules available"
-
-    user_options = [
-        ('output=', 'O', 'output directory'),
-    ]
-
-    def initialize_options(self):
-        pass
-
-    def finalize_options(self):
-        pass
-
-    def run(self):
-        print("auto-generating API documentation")
-        with open("docs/api.rst", "w") as doc:
-            doc.write("""
-.. IMPORTANT: this file is auto-generated by "setup.py build_api", do not edit!
-
-
-API Documentation
-=================
-""")
-            for mod in sorted(glob('borg/*.py') + glob('borg/*.pyx')):
-                print("examining module %s" % mod)
-                mod = mod.replace('.pyx', '').replace('.py', '').replace('/', '.')
-                if "._" not in mod:
-                    doc.write("""
-.. automodule:: %s
-    :members:
-    :undoc-members:
-""" % mod)
-
-
 cmdclass = {
     'build_ext': build_ext,
-    'build_api': build_api,
     'build_usage': build_usage,
     'sdist': Sdist
 }