Merge ~ltrager/maas:lp1869958_2.6 into maas:2.6

[Lee Trager]

Backport of 9424d23 LP: #1869958 - Run fio using the native block size of the disk.

[Lee Trager (ltrager)]

Approved in https://code.launchpad.net/~ltrager/maas/+git/maas/+merge/383741

review: Approve

diff --git a/src/metadataserver/builtin_scripts/fio.py b/src/metadataserver/builtin_scripts/fio.py
index 451e278..9ab18d5 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
@@ -78,9 +78,17 @@ import yaml
 # When given --output-format=normal,json fio > 3 outputs both normal
 # and json format. Older versions just output the normal format.
 CMD = [
-    'sudo', '-n', 'fio', '--randrepeat=1', '--ioengine=libaio',
-    '--direct=1', '--gtod_reduce=1', '--name=fio_test', '--bs=4k',
-    '--iodepth=64', '--size=4G', '--output-format=normal,json'
+    "sudo",
+    "-n",
+    "fio",
+    "--randrepeat=1",
+    "--ioengine=libaio",
+    "--direct=1",
+    "--gtod_reduce=1",
+    "--name=fio_test",
+    "--iodepth=64",
+    "--size=4G",
+    "--output-format=normal,json",
 ]
 
 
@@ -99,6 +107,13 @@ REGEX = re.compile(r'''
 ''', re.MULTILINE | re.DOTALL | re.VERBOSE)
 
 
+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)
@@ -162,7 +177,8 @@ def run_fio(blockdevice):
 
     Performs random and sequential read and write tests.
     """
-    CMD.append('--filename=%s' % blockdevice)
+    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 be7876f..dc624ab 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."""
@@ -172,10 +172,12 @@ class TestFioTestRunFio(MAASTestCase):
 
     def setUp(self):
         super().setUp()
-        self.mock_print = self.patch(fio, 'print')
-        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_print = self.patch(fio, "print")
+        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)