| 1 | #!/usr/bin/env python3 |
| 2 | # |
| 3 | # Test to compare performance of write requests for two qemu-img binary files. |
| 4 | # |
| 5 | # The idea of the test comes from intention to check the benefit of c8bb23cbdbe |
| 6 | # "qcow2: skip writing zero buffers to empty COW areas". |
| 7 | # |
| 8 | # Copyright (c) 2020 Virtuozzo International GmbH. |
| 9 | # |
| 10 | # This program is free software; you can redistribute it and/or modify |
| 11 | # it under the terms of the GNU General Public License as published by |
| 12 | # the Free Software Foundation; either version 2 of the License, or |
| 13 | # (at your option) any later version. |
| 14 | # |
| 15 | # This program is distributed in the hope that it will be useful, |
| 16 | # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | # GNU General Public License for more details. |
| 19 | # |
| 20 | # You should have received a copy of the GNU General Public License |
| 21 | # along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 22 | # |
| 23 | |
| 24 | |
| 25 | import sys |
| 26 | import os |
| 27 | import subprocess |
| 28 | import simplebench |
| 29 | from results_to_text import results_to_text |
| 30 | |
| 31 | |
| 32 | def bench_func(env, case): |
| 33 | """ Handle one "cell" of benchmarking table. """ |
| 34 | return bench_write_req(env['qemu_img'], env['image_name'], |
| 35 | case['block_size'], case['block_offset'], |
| 36 | case['cluster_size']) |
| 37 | |
| 38 | |
| 39 | def qemu_img_pipe(*args): |
| 40 | '''Run qemu-img and return its output''' |
| 41 | subp = subprocess.Popen(list(args), |
| 42 | stdout=subprocess.PIPE, |
| 43 | stderr=subprocess.STDOUT, |
| 44 | universal_newlines=True) |
| 45 | exitcode = subp.wait() |
| 46 | if exitcode < 0: |
| 47 | sys.stderr.write('qemu-img received signal %i: %s\n' |
| 48 | % (-exitcode, ' '.join(list(args)))) |
| 49 | return subp.communicate()[0] |
| 50 | |
| 51 | |
| 52 | def bench_write_req(qemu_img, image_name, block_size, block_offset, |
| 53 | cluster_size): |
| 54 | """Benchmark write requests |
| 55 | |
| 56 | The function creates a QCOW2 image with the given path/name. Then it runs |
| 57 | the 'qemu-img bench' command and makes series of write requests on the |
| 58 | image clusters. Finally, it returns the total time of the write operations |
| 59 | on the disk. |
| 60 | |
| 61 | qemu_img -- path to qemu_img executable file |
| 62 | image_name -- QCOW2 image name to create |
| 63 | block_size -- size of a block to write to clusters |
| 64 | block_offset -- offset of the block in clusters |
| 65 | cluster_size -- size of the image cluster |
| 66 | |
| 67 | Returns {'seconds': int} on success and {'error': str} on failure. |
| 68 | Return value is compatible with simplebench lib. |
| 69 | """ |
| 70 | |
| 71 | if not os.path.isfile(qemu_img): |
| 72 | print(f'File not found: {qemu_img}') |
| 73 | sys.exit(1) |
| 74 | |
| 75 | image_dir = os.path.dirname(os.path.abspath(image_name)) |
| 76 | if not os.path.isdir(image_dir): |
| 77 | print(f'Path not found: {image_name}') |
| 78 | sys.exit(1) |
| 79 | |
| 80 | image_size = 1024 * 1024 * 1024 |
| 81 | |
| 82 | args_create = [qemu_img, 'create', '-f', 'qcow2', '-o', |
| 83 | f'cluster_size={cluster_size}', |
| 84 | image_name, str(image_size)] |
| 85 | |
| 86 | count = int(image_size / cluster_size) - 1 |
| 87 | step = str(cluster_size) |
| 88 | |
| 89 | args_bench = [qemu_img, 'bench', '-w', '-n', '-t', 'none', '-c', |
| 90 | str(count), '-s', f'{block_size}', '-o', str(block_offset), |
| 91 | '-S', step, '-f', 'qcow2', image_name] |
| 92 | |
| 93 | try: |
| 94 | qemu_img_pipe(*args_create) |
| 95 | except OSError as e: |
| 96 | os.remove(image_name) |
| 97 | return {'error': 'qemu_img create failed: ' + str(e)} |
| 98 | |
| 99 | try: |
| 100 | ret = qemu_img_pipe(*args_bench) |
| 101 | except OSError as e: |
| 102 | os.remove(image_name) |
| 103 | return {'error': 'qemu_img bench failed: ' + str(e)} |
| 104 | |
| 105 | os.remove(image_name) |
| 106 | |
| 107 | if 'seconds' in ret: |
| 108 | ret_list = ret.split() |
| 109 | index = ret_list.index('seconds.') |
| 110 | return {'seconds': float(ret_list[index-1])} |
| 111 | else: |
| 112 | return {'error': 'qemu_img bench failed: ' + ret} |
| 113 | |
| 114 | |
| 115 | if __name__ == '__main__': |
| 116 | |
| 117 | if len(sys.argv) < 4: |
| 118 | program = os.path.basename(sys.argv[0]) |
| 119 | print(f'USAGE: {program} <path to qemu-img binary file> ' |
| 120 | '<path to another qemu-img to compare performance with> ' |
| 121 | '<full or relative name for QCOW2 image to create>') |
| 122 | exit(1) |
| 123 | |
| 124 | # Test-cases are "rows" in benchmark resulting table, 'id' is a caption |
| 125 | # for the row, other fields are handled by bench_func. |
| 126 | test_cases = [ |
| 127 | { |
| 128 | 'id': '<cluster front>', |
| 129 | 'block_size': 4096, |
| 130 | 'block_offset': 0, |
| 131 | 'cluster_size': 1048576 |
| 132 | }, |
| 133 | { |
| 134 | 'id': '<cluster middle>', |
| 135 | 'block_size': 4096, |
| 136 | 'block_offset': 524288, |
| 137 | 'cluster_size': 1048576 |
| 138 | }, |
| 139 | { |
| 140 | 'id': '<cross cluster>', |
| 141 | 'block_size': 1048576, |
| 142 | 'block_offset': 4096, |
| 143 | 'cluster_size': 1048576 |
| 144 | }, |
| 145 | { |
| 146 | 'id': '<cluster 64K>', |
| 147 | 'block_size': 4096, |
| 148 | 'block_offset': 0, |
| 149 | 'cluster_size': 65536 |
| 150 | }, |
| 151 | ] |
| 152 | |
| 153 | # Test-envs are "columns" in benchmark resulting table, 'id is a caption |
| 154 | # for the column, other fields are handled by bench_func. |
| 155 | # Set the paths below to desired values |
| 156 | test_envs = [ |
| 157 | { |
| 158 | 'id': '<qemu-img binary 1>', |
| 159 | 'qemu_img': f'{sys.argv[1]}', |
| 160 | 'image_name': f'{sys.argv[3]}' |
| 161 | }, |
| 162 | { |
| 163 | 'id': '<qemu-img binary 2>', |
| 164 | 'qemu_img': f'{sys.argv[2]}', |
| 165 | 'image_name': f'{sys.argv[3]}' |
| 166 | }, |
| 167 | ] |
| 168 | |
| 169 | result = simplebench.bench(bench_func, test_envs, test_cases, count=3, |
| 170 | initial_run=False) |
| 171 | print(results_to_text(result)) |