#!/usr/bin/env python3
"""
Performance tests using fsck.ext2 on a test file.
It can be tuned with the following environment variables:
- TEST_FILE: The name of the file used for testing. By default, ".test_fs".
- TEST_FILE_SIZE_MB: The size of the test file, in megabytes. Only used if
the file doesn't exist. Default: 10.
- VERBOSE: Show verbose output (from 0 to 2). Default: 0.
- LD_LIBRARY_PATH: Library path to pass on to the subcommands.
Default: <directory of this file>/../libfiu/, which is usually the one
containing the current build.
"""
import os
import sys
import subprocess
import time
test_file = os.environ.get('TEST_FILE', '.test_fs')
test_file_size = int(os.environ.get('TEST_FILE_SIZE_MB', 10))
ld_library_path = os.environ.get('LD_LIBRARY_PATH',
os.path.abspath(
os.path.abspath(os.path.dirname(sys.argv[0]))
+ '/../libfiu/'))
verbose = int(os.environ.get('VERBOSE', 0))
dev_null = open('/dev/null', 'w')
def run_child(name, args, stdout = dev_null, stderr = dev_null):
"""Runs the subprocess, returns the Popen object."""
env = dict(os.environ)
env['LD_LIBRARY_PATH'] = ld_library_path
if verbose and stdout == stderr == dev_null:
stdout = stderr = None
child = subprocess.Popen(args, env = env,
stdout = stdout, stderr = stderr)
return child
def run_and_time(name, args):
"""Run the given arguments, print the times."""
start = time.time()
child = run_child(name, args)
_, status, rusage = os.wait4(child.pid, 0)
end = time.time()
if verbose == 2:
print('Ran %s -> %d' % (args, status))
if status != 0:
print('Error running %s: %s' % (args[0], status))
raise RuntimeError
print('%-10s u:%.3f s:%.3f r:%.3f' % (
name, rusage.ru_utime, rusage.ru_stime, end - start))
def run_fsck(name, fiu_args):
"""Runs an fsck with the given fiu arguments."""
child = run_child(name,
["fiu-run", "-x"] + fiu_args
+ "fsck.ext2 -n -t -f".split() + [test_file],
stdout = subprocess.PIPE,
stderr = subprocess.PIPE)
stdout, stderr = child.communicate()
if child.returncode != 0:
print('Error running fsck: %s' % child.returncode)
raise RuntimeError
# Find the times reported by fsck.
# Not very robust, but useful as it measures the real program time run,
# and not the startup overhead.
# The line looks like:
# Memory used: 560k/0k (387k/174k), time: 2.18/ 2.17/ 0.00
user_time = sys_time = real_time = -1
for l in stdout.split('\n'):
if not l.startswith("Memory used"):
continue
times = l.split(':')[-1].split('/')
times = [s.strip() for s in times]
if len(times) != 3:
continue
real_time = float(times[0])
user_time = float(times[1])
sys_time = float(times[2])
break
print('%-10s u:%.3f s:%.3f r:%.3f' % (
name, user_time, sys_time, real_time))
def check_test_file():
if os.path.exists(test_file):
return
with open(test_file, 'w') as fd:
fd.truncate(test_file_size * 1024 * 1024)
retcode = subprocess.call(
["mkfs.ext2", "-F", test_file],
stdout = open('/dev/null', 'w'))
if retcode != 0:
print('Error running mkfs.ext2:', retcode)
return
if __name__ == '__main__':
check_test_file()
run_and_time("base", "fsck.ext2 -n -f".split() + [test_file])
# 1 all-matching wildcard.
run_fsck("w1", ["-c", "enable_random name=*,probability=0"])
# 1k final failure points, no matches.
args = []
for i in range(1000):
args += ["-c", "enable_random name=none/%d,probability=0" % i]
run_fsck("f1k", args)
# 1k wildcard failure points, no matches.
args = []
for i in range(1000):
args += ["-c", "enable_random name=none/%d/*,probability=0" % i]
run_fsck("w1k", args)
# 1k wildcarded failure points, and 1 match.
args = []
for i in range(1000):
args += ["-c", "enable_random name=none/%d/*,probability=0" % i]
args += ["-c", "enable_random name=*,probability=0"]
run_fsck("w1k+1", args)
# 1k final failure points, *all* matches.
args = []
for i in range(1000):
args += ["-c", "enable_random name=*,probability=0"]
run_fsck("m1k", args)