linux/tools/testing/selftests/damon/damos_quota.py
SeongJae Park 51f58c9da1 selftests/damon: add a test for DAMOS quota
Add a selftest for verifying the DAMOS quota feature.  The test is very
similar to sysfs_update_schemes_tried_regions_wss_estimation.py.  It
starts an artificial workload of 20 MiB working set, run DAMON to find the
working set size, but with 1 MiB/100 ms size quota.  Then, it collect the
DAMON-found working set size every 100 ms and check if the quota was
always applied as expected.  For the confirmation, the tests shows the
stat-applied region size and the qt_exceeds stat.

Link: https://lkml.kernel.org/r/20240207203134.69976-5-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 10:24:56 -08:00

68 lines
2.2 KiB
Python

#!/usr/bin/env python3
# SPDX-License-Identifier: GPL-2.0
import subprocess
import time
import _damon_sysfs
def main():
# access two 10 MiB memory regions, 2 second per each
sz_region = 10 * 1024 * 1024
proc = subprocess.Popen(['./access_memory', '2', '%d' % sz_region, '2000'])
# Set quota up to 1 MiB per 100 ms
sz_quota = 1024 * 1024 # 1 MiB
quota_reset_interval = 100 # 100 ms
kdamonds = _damon_sysfs.Kdamonds([_damon_sysfs.Kdamond(
contexts=[_damon_sysfs.DamonCtx(
ops='vaddr',
targets=[_damon_sysfs.DamonTarget(pid=proc.pid)],
schemes=[_damon_sysfs.Damos(
access_pattern=_damon_sysfs.DamosAccessPattern(
# >= 25% access rate, >= 200ms age
nr_accesses=[5, 20], age=[2, 2**64 - 1]),
quota=_damon_sysfs.DamosQuota(
sz=sz_quota, reset_interval_ms=quota_reset_interval)
)] # schemes
)] # contexts
)]) # kdamonds
err = kdamonds.start()
if err != None:
print('kdamond start failed: %s' % err)
exit(1)
wss_collected = []
nr_quota_exceeds = 0
while proc.poll() == None:
time.sleep(0.1)
err = kdamonds.kdamonds[0].update_schemes_tried_bytes()
if err != None:
print('tried bytes update failed: %s' % err)
exit(1)
err = kdamonds.kdamonds[0].update_schemes_stats()
if err != None:
print('stats update failed: %s' % err)
exit(1)
scheme = kdamonds.kdamonds[0].contexts[0].schemes[0]
wss_collected.append(scheme.tried_bytes)
nr_quota_exceeds = scheme.stats.qt_exceeds
wss_collected.sort()
for wss in wss_collected:
if wss > sz_quota:
print('quota is not kept: %s > %s' % (wss, sz_quota))
print('collected samples are as below')
print('\n'.join(['%d' % wss for wss in wss_collected]))
exit(1)
if nr_quota_exceeds < len(wss_collected):
print('quota is not always exceeded: %d > %d' %
(len(wss_collected), nr_quota_exceeds))
exit(1)
if __name__ == '__main__':
main()