Merge ~ltrager/maas:lp1869958 into maas:master

[Lee Trager]

LP: #1869958 - Run fio using the native block size of the disk.

[MAAS Lander (maas-lander)]

UNIT TESTS
-b lp1869958 lp:~ltrager/maas/+git/maas into -b master lp:~maas-committers/maas

STATUS: SUCCESS
COMMIT: c5fb0ccba014f601c489d151f7d8361d04828af0

review: Approve

[Dougal Matthews (d0ugal)]

LGTM, I wonder if we ever need the old default?

review: Approve

[Lee Trager (ltrager)]

Linus is really strict about not breaking compatibility with user space so we should always have a value. The old value was arbitrary so I don't think there is a need to keep it around.

diff --git a/src/metadataserver/builtin_scripts/fio.py b/src/metadataserver/builtin_scripts/fio.py
index 71d2d70..da3d218 100644
--- a/src/metadataserver/builtin_scripts/fio.py
+++ b/src/metadataserver/builtin_scripts/fio.py
@@ -5,7 +5,7 @@
 # Author: Newell Jensen <[e-mail]>
 #         Lee Trager <[e-mail]>
 #
-# Copyright (C) 2017-2018 Canonical
+# Copyright (C) 2017-2020 Canonical
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU Affero General Public License as
@@ -83,7 +83,6 @@ CMD = [
     "--direct=1",
     "--gtod_reduce=1",
     "--name=fio_test",
-    "--bs=4k",
     "--iodepth=64",
     "--size=4G",
     "--output-format=normal,json",
@@ -108,6 +107,13 @@ REGEX = re.compile(
 )
 
 
+def get_blocksize(blockdevice):
+    """Return the block size of the block device."""
+    blockname = os.path.basename(blockdevice)
+    with open("/sys/block/%s/queue/physical_block_size" % blockname, "r") as f:
+        return int(f.read())
+
+
 def run_cmd(readwrite, result_break=True):
     """Execute `CMD` and return output or exit if error."""
     cmd = deepcopy(CMD)
@@ -163,6 +169,7 @@ def run_fio(blockdevice):
     Performs random and sequential read and write tests.
     """
     CMD.append("--filename=%s" % blockdevice)
+    CMD.append("--bs=%s" % get_blocksize(blockdevice))
     random_read = run_cmd("randread")
     sequential_read = run_cmd("read")
     random_write = run_cmd("randwrite")
diff --git a/src/metadataserver/builtin_scripts/tests/test_fio.py b/src/metadataserver/builtin_scripts/tests/test_fio.py
index 24a3702..25f004e 100644
--- a/src/metadataserver/builtin_scripts/tests/test_fio.py
+++ b/src/metadataserver/builtin_scripts/tests/test_fio.py
@@ -1,4 +1,4 @@
-# Copyright 2017-2018 Canonical Ltd.  This software is licensed under the
+# Copyright 2017-2020 Canonical Ltd.  This software is licensed under the
 # GNU Affero General Public License version 3 (see the file LICENSE).
 
 """Test builtin_script fio."""
@@ -202,6 +202,8 @@ class TestFioTestRunFio(MAASTestCase):
         self.mock_stdout_write = self.patch(fio.sys.stdout, "write")
         self.mock_stderr_write = self.patch(fio.sys.stderr, "write")
         self.mock_check_output = self.patch(fio, "check_output")
+        self.mock_get_blocksize = self.patch(fio, "get_blocksize")
+        self.mock_get_blocksize.return_value = 512
 
     def test_run_fio_writes_yaml_file(self):
         tmp_path = Path(self.useFixture(TempDirectory()).path)