aboutsummaryrefslogtreecommitdiffstats
path: root/tools/cgroup/iocost_coef_gen.py
blob: df17a2ae80e5f900576dc0a55af0c2544db6365b (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
#!/usr/bin/env python3
#
# Copyright (C) 2019 Tejun Heo <tj@kernel.org>
# Copyright (C) 2019 Andy Newell <newella@fb.com>
# Copyright (C) 2019 Facebook

desc = """
Generate linear IO cost model coefficients used by the blk-iocost
controller.  If the target raw testdev is specified, destructive tests
are performed against the whole device; otherwise, on
./iocost-coef-fio.testfile.  The result can be written directly to
/sys/fs/cgroup/io.cost.model.

On high performance devices, --numjobs > 1 is needed to achieve
saturation.

See Documentation/admin-guide/cgroup-v2.rst and block/blk-iocost.c
for more details.
"""

import argparse
import re
import json
import glob
import os
import sys
import atexit
import shutil
import tempfile
import subprocess

parser = argparse.ArgumentParser(description=desc,
                                 formatter_class=argparse.RawTextHelpFormatter)
parser.add_argument('--testdev', metavar='DEV',
                    help='Raw block device to use for testing, ignores --testfile-size')
parser.add_argument('--testfile-size-gb', type=float, metavar='GIGABYTES', default=16,
                    help='Testfile size in gigabytes (default: %(default)s)')
parser.add_argument('--duration', type=int, metavar='SECONDS', default=120,
                    help='Individual test run duration in seconds (default: %(default)s)')
parser.add_argument('--seqio-block-mb', metavar='MEGABYTES', type=int, default=128,
                    help='Sequential test block size in megabytes (default: %(default)s)')
parser.add_argument('--seq-depth', type=int, metavar='DEPTH', default=64,
                    help='Sequential test queue depth (default: %(default)s)')
parser.add_argument('--rand-depth', type=int, metavar='DEPTH', default=64,
                    help='Random test queue depth (default: %(default)s)')
parser.add_argument('--numjobs', type=int, metavar='JOBS', default=1,
                    help='Number of parallel fio jobs to run (default: %(default)s)')
parser.add_argument('--quiet', action='store_true')
parser.add_argument('--verbose', action='store_true')

def info(msg):
    if not args.quiet:
        print(msg)

def dbg(msg):
    if args.verbose and not args.quiet:
        print(msg)

# determine ('DEVNAME', 'MAJ:MIN') for @path
def dir_to_dev(path):
    # find the block device the current directory is on
    devname = subprocess.run(f'findmnt -nvo SOURCE -T{path}',
                             stdout=subprocess.PIPE, shell=True).stdout
    devname = os.path.basename(devname).decode('utf-8').strip()

    # partition -> whole device
    parents = glob.glob('/sys/block/*/' + devname)
    if len(parents):
        devname = os.path.basename(os.path.dirname(parents[0]))
    rdev = os.stat(f'/dev/{devname}').st_rdev
    return (devname, f'{os.major(rdev)}:{os.minor(rdev)}')

def create_testfile(path, size):
    global args

    if os.path.isfile(path) and os.stat(path).st_size == size:
        return

    info(f'Creating testfile {path}')
    subprocess.check_call(f'rm -f {path}', shell=True)
    subprocess.check_call(f'touch {path}', shell=True)
    subprocess.call(f'chattr +C {path}', shell=True)
    subprocess.check_call(
        f'pv -s {size} -pr /dev/urandom {"-q" if args.quiet else ""} | '
        f'dd of={path} count={size} '
        f'iflag=count_bytes,fullblock oflag=direct bs=16M status=none',
        shell=True)

def run_fio(testfile, duration, iotype, iodepth, blocksize, jobs):
    global args

    eta = 'never' if args.quiet else 'always'
    outfile = tempfile.NamedTemporaryFile()
    cmd = (f'fio --direct=1 --ioengine=libaio --name=coef '
           f'--filename={testfile} --runtime={round(duration)} '
           f'--readwrite={iotype} --iodepth={iodepth} --blocksize={blocksize} '
           f'--eta={eta} --output-format json --output={outfile.name} '
           f'--time_based --numjobs={jobs}')
    if args.verbose:
        dbg(f'Running {cmd}')
    subprocess.check_call(cmd, shell=True)
    with open(outfile.name, 'r') as f:
        d = json.loads(f.read())
    return sum(j['read']['bw_bytes'] + j['write']['bw_bytes'] for j in d['jobs'])

def restore_elevator_nomerges():
    global elevator_path, nomerges_path, elevator, nomerges

    info(f'Restoring elevator to {elevator} and nomerges to {nomerges}')
    with open(elevator_path, 'w') as f:
        f.write(elevator)
    with open(nomerges_path, 'w') as f:
        f.write(nomerges)


args = parser.parse_args()

missing = False
for cmd in [ 'findmnt', 'pv', 'dd', 'fio' ]:
    if not shutil.which(cmd):
        print(f'Required command "{cmd}" is missing', file=sys.stderr)
        missing = True
if missing:
    sys.exit(1)

if args.testdev:
    devname = os.path.basename(args.testdev)
    rdev = os.stat(f'/dev/{devname}').st_rdev
    devno = f'{os.major(rdev)}:{os.minor(rdev)}'
    testfile = f'/dev/{devname}'
    info(f'Test target: {devname}({devno})')
else:
    devname, devno = dir_to_dev('.')
    testfile = 'iocost-coef-fio.testfile'
    testfile_size = int(args.testfile_size_gb * 2 ** 30)
    create_testfile(testfile, testfile_size)
    info(f'Test target: {testfile} on {devname}({devno})')

elevator_path = f'/sys/block/{devname}/queue/scheduler'
nomerges_path = f'/sys/block/{devname}/queue/nomerges'

with open(elevator_path, 'r') as f:
    elevator = re.sub(r'.*\[(.*)\].*', r'\1', f.read().strip())
with open(nomerges_path, 'r') as f:
    nomerges = f.read().strip()

info(f'Temporarily disabling elevator and merges')
atexit.register(restore_elevator_nomerges)
with open(elevator_path, 'w') as f:
    f.write('none')
with open(nomerges_path, 'w') as f:
    f.write('1')

info('Determining rbps...')
rbps = run_fio(testfile, args.duration, 'read',
               1, args.seqio_block_mb * (2 ** 20), args.numjobs)
info(f'\nrbps={rbps}, determining rseqiops...')
rseqiops = round(run_fio(testfile, args.duration, 'read',
                         args.seq_depth, 4096, args.numjobs) / 4096)
info(f'\nrseqiops={rseqiops}, determining rrandiops...')
rrandiops = round(run_fio(testfile, args.duration, 'randread',
                          args.rand_depth, 4096, args.numjobs) / 4096)
info(f'\nrrandiops={rrandiops}, determining wbps...')
wbps = run_fio(testfile, args.duration, 'write',
               1, args.seqio_block_mb * (2 ** 20), args.numjobs)
info(f'\nwbps={wbps}, determining wseqiops...')
wseqiops = round(run_fio(testfile, args.duration, 'write',
                         args.seq_depth, 4096, args.numjobs) / 4096)
info(f'\nwseqiops={wseqiops}, determining wrandiops...')
wrandiops = round(run_fio(testfile, args.duration, 'randwrite',
                          args.rand_depth, 4096, args.numjobs) / 4096)
info(f'\nwrandiops={wrandiops}')
restore_elevator_nomerges()
atexit.unregister(restore_elevator_nomerges)
info('')

print(f'{devno} rbps={rbps} rseqiops={rseqiops} rrandiops={rrandiops} '
      f'wbps={wbps} wseqiops={wseqiops} wrandiops={wrandiops}')