[4/8] selftests/damon: add a test for DAMOS quota
Commit Message
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.
Signed-off-by: SeongJae Park <sj@kernel.org>
---
tools/testing/selftests/damon/Makefile | 1 +
tools/testing/selftests/damon/damos_quota.py | 67 ++++++++++++++++++++
2 files changed, 68 insertions(+)
create mode 100755 tools/testing/selftests/damon/damos_quota.py
@@ -12,6 +12,7 @@ TEST_PROGS += debugfs_rm_non_contexts.sh
TEST_PROGS += sysfs.sh sysfs_update_removed_scheme_dir.sh
TEST_PROGS += sysfs_update_schemes_tried_regions_hang.py
TEST_PROGS += sysfs_update_schemes_tried_regions_wss_estimation.py
+TEST_PROGS += damos_quota.py
TEST_PROGS += reclaim.sh lru_sort.sh
include ../lib.mk
new file mode 100755
@@ -0,0 +1,67 @@
+#!/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()