xref: /linux/tools/testing/selftests/damon/sysfs_update_schemes_tried_regions_wss_estimation.py (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1#!/usr/bin/env python3
2# SPDX-License-Identifier: GPL-2.0
3
4import subprocess
5import time
6
7import _damon_sysfs
8
9def main():
10    # access two 10 MiB memory regions, 2 second per each
11    sz_region = 10 * 1024 * 1024
12    proc = subprocess.Popen(['./access_memory', '2', '%d' % sz_region, '2000'])
13    kdamonds = _damon_sysfs.Kdamonds([_damon_sysfs.Kdamond(
14            contexts=[_damon_sysfs.DamonCtx(
15                ops='vaddr',
16                targets=[_damon_sysfs.DamonTarget(pid=proc.pid)],
17                schemes=[_damon_sysfs.Damos(
18                    access_pattern=_damon_sysfs.DamosAccessPattern(
19                        # >= 25% access rate, >= 200ms age
20                        nr_accesses=[5, 20], age=[2, 2**64 - 1]))] # schemes
21                )] # contexts
22            )]) # kdamonds
23
24    err = kdamonds.start()
25    if err != None:
26        print('kdamond start failed: %s' % err)
27        exit(1)
28
29    wss_collected = []
30    while proc.poll() == None:
31        time.sleep(0.1)
32        err = kdamonds.kdamonds[0].update_schemes_tried_bytes()
33        if err != None:
34            print('tried bytes update failed: %s' % err)
35            exit(1)
36
37        wss_collected.append(
38                kdamonds.kdamonds[0].contexts[0].schemes[0].tried_bytes)
39
40    wss_collected.sort()
41    acceptable_error_rate = 0.2
42    for percentile in [50, 75]:
43        sample = wss_collected[int(len(wss_collected) * percentile / 100)]
44        error_rate = abs(sample - sz_region) / sz_region
45        print('%d-th percentile (%d) error %f' %
46                (percentile, sample, error_rate))
47        if error_rate > acceptable_error_rate:
48            print('the error rate is not acceptable (> %f)' %
49                    acceptable_error_rate)
50            print('samples are as below')
51            print('\n'.join(['%d' % wss for wss in wss_collected]))
52            exit(1)
53
54if __name__ == '__main__':
55    main()
56