scripts/simplebench/bench_prealloc.py

   1 #!/usr/bin/env python3
   2 #
   3 # Benchmark preallocate filter
   4 #
   5 # Copyright (c) 2020 Virtuozzo International GmbH.
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 2 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 #
  20
  21
  22 import sys
  23 import os
  24 import subprocess
  25 import re
  26 import json
  27
  28 import simplebench
  29 from results_to_text import results_to_text
  30
  31
  32 def qemu_img_bench(args):
  33     p = subprocess.run(args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT,
  34                        universal_newlines=True)
  35
  36     if p.returncode == 0:
  37         try:
  38             m = re.search(r'Run completed in (\d+.\d+) seconds.', p.stdout)
  39             return {'seconds': float(m.group(1))}
  40         except Exception:
  41             return {'error': f'failed to parse qemu-img output: {p.stdout}'}
  42     else:
  43         return {'error': f'qemu-img failed: {p.returncode}: {p.stdout}'}
  44
  45
  46 def bench_func(env, case):
  47     fname = f"{case['dir']}/prealloc-test.qcow2"
  48     try:
  49         os.remove(fname)
  50     except OSError:
  51         pass
  52
  53     subprocess.run([env['qemu-img-binary'], 'create', '-f', 'qcow2', fname,
  54                    '16G'], stdout=subprocess.DEVNULL,
  55                    stderr=subprocess.DEVNULL, check=True)
  56
  57     args = [env['qemu-img-binary'], 'bench', '-c', str(case['count']),
  58             '-d', '64', '-s', case['block-size'], '-t', 'none', '-n', '-w']
  59     if env['prealloc']:
  60         args += ['--image-opts',
  61                  'driver=qcow2,file.driver=preallocate,file.file.driver=file,'
  62                  f'file.file.filename={fname}']
  63     else:
  64         args += ['-f', 'qcow2', fname]
  65
  66     return qemu_img_bench(args)
  67
  68
  69 def auto_count_bench_func(env, case):
  70     case['count'] = 100
  71     while True:
  72         res = bench_func(env, case)
  73         if 'error' in res:
  74             return res
  75
  76         if res['seconds'] >= 1:
  77             break
  78
  79         case['count'] *= 10
  80
  81     if res['seconds'] < 5:
  82         case['count'] = round(case['count'] * 5 / res['seconds'])
  83         res = bench_func(env, case)
  84         if 'error' in res:
  85             return res
  86
  87     res['iops'] = case['count'] / res['seconds']
  88     return res
  89
  90
  91 if __name__ == '__main__':
  92     if len(sys.argv) < 2:
  93         print(f'USAGE: {sys.argv[0]} <qemu-img binary> '
  94               'DISK_NAME:DIR_PATH ...')
  95         exit(1)
  96
  97     qemu_img = sys.argv[1]
  98
  99     envs = [
 100         {
 101             'id': 'no-prealloc',
 102             'qemu-img-binary': qemu_img,
 103             'prealloc': False
 104         },
 105         {
 106             'id': 'prealloc',
 107             'qemu-img-binary': qemu_img,
 108             'prealloc': True
 109         }
 110     ]
 111
 112     aligned_cases = []
 113     unaligned_cases = []
 114
 115     for disk in sys.argv[2:]:
 116         name, path = disk.split(':')
 117         aligned_cases.append({
 118             'id': f'{name}, aligned sequential 16k',
 119             'block-size': '16k',
 120             'dir': path
 121         })
 122         unaligned_cases.append({
 123             'id': f'{name}, unaligned sequential 64k',
 124             'block-size': '16k',
 125             'dir': path
 126         })
 127
 128     result = simplebench.bench(auto_count_bench_func, envs,
 129                                aligned_cases + unaligned_cases, count=5)
 130     print(results_to_text(result))
 131     with open('results.json', 'w') as f:
 132         json.dump(result, f, indent=4)