qemu

img_bench_templater.py (3388B)

---

 #!/usr/bin/env python3
 #
 # Process img-bench test templates
 #
 # Copyright (c) 2021 Virtuozzo International GmbH.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation; either version 2 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 
 
 import sys
 import subprocess
 import re
 import json
 
 import simplebench
 from results_to_text import results_to_text
 from table_templater import Templater
 
 
 def bench_func(env, case):
     test = templater.gen(env['data'], case['data'])
 
     p = subprocess.run(test, shell=True, stdout=subprocess.PIPE,
                        stderr=subprocess.STDOUT, universal_newlines=True)
 
     if p.returncode == 0:
         try:
             m = re.search(r'Run completed in (\d+.\d+) seconds.', p.stdout)
             return {'seconds': float(m.group(1))}
         except Exception:
             return {'error': f'failed to parse qemu-img output: {p.stdout}'}
     else:
         return {'error': f'qemu-img failed: {p.returncode}: {p.stdout}'}
 
 
 if __name__ == '__main__':
     if len(sys.argv) > 1:
         print("""
 Usage: img_bench_templater.py < path/to/test-template.sh
 
 This script generates performance tests from a test template (example below),
 runs them, and displays the results in a table. The template is read from
 stdin.  It must be written in bash and end with a `qemu-img bench` invocation
 (whose result is parsed to get the test instance’s result).
 
 Use the following syntax in the template to create the various different test
 instances:
 
   column templating: {var1|var2|...} - test will use different values in
   different columns. You may use several {} constructions in the test, in this
   case product of all choice-sets will be used.
 
   row templating: [var1|var2|...] - similar thing to define rows (test-cases)
 
 Test template example:
 
 Assume you want to compare two qemu-img binaries, called qemu-img-old and
 qemu-img-new in your build directory in two test-cases with 4K writes and 64K
 writes. The template may look like this:
 
 qemu_img=/path/to/qemu/build/qemu-img-{old|new}
 $qemu_img create -f qcow2 /ssd/x.qcow2 1G
 $qemu_img bench -c 100 -d 8 [-s 4K|-s 64K] -w -t none -n /ssd/x.qcow2
 
 When passing this to stdin of img_bench_templater.py, the resulting comparison
 table will contain two columns (for two binaries) and two rows (for two
 test-cases).
 
 In addition to displaying the results, script also stores results in JSON
 format into results.json file in current directory.
 """)
         sys.exit()
 
     templater = Templater(sys.stdin.read())
 
     envs = [{'id': ' / '.join(x), 'data': x} for x in templater.columns]
     cases = [{'id': ' / '.join(x), 'data': x} for x in templater.rows]
 
     result = simplebench.bench(bench_func, envs, cases, count=5,
                                initial_run=False)
     print(results_to_text(result))
     with open('results.json', 'w') as f:
         json.dump(result, f, indent=4)