tools/testing/selftests/damon/damos_apply_interval.py

   1 #!/usr/bin/env python3
   2 # SPDX-License-Identifier: GPL-2.0
   3
   4 import subprocess
   5 import time
   6
   7 import _damon_sysfs
   8
   9 def 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
  14     # Set quota up to 1 MiB per 100 ms
  15     kdamonds = _damon_sysfs.Kdamonds([_damon_sysfs.Kdamond(
  16             contexts=[_damon_sysfs.DamonCtx(
  17                 ops='vaddr',
  18                 targets=[_damon_sysfs.DamonTarget(pid=proc.pid)],
  19                 schemes=[
  20                     _damon_sysfs.Damos(
  21                         access_pattern=_damon_sysfs.DamosAccessPattern(
  22                             # >= 25% access rate, >= 200ms age
  23                             nr_accesses=[5, 20], age=[2, 2**64 - 1]),
  24                         # aggregation interval (100 ms) is used
  25                         apply_interval_us=0),
  26                     # use 10ms apply interval
  27                     _damon_sysfs.Damos(
  28                         access_pattern=_damon_sysfs.DamosAccessPattern(
  29                             # >= 25% access rate, >= 200ms age
  30                             nr_accesses=[5, 20], age=[2, 2**64 - 1]),
  31                         # explicitly set 10 ms apply interval
  32                         apply_interval_us=10 * 1000)
  33                     ] # schemes
  34                 )] # contexts
  35             )]) # kdamonds
  36
  37     err = kdamonds.start()
  38     if err != None:
  39         print('kdamond start failed: %s' % err)
  40         exit(1)
  41
  42     wss_collected = []
  43     nr_quota_exceeds = 0
  44     while proc.poll() == None:
  45         time.sleep(0.1)
  46         err = kdamonds.kdamonds[0].update_schemes_stats()
  47         if err != None:
  48             print('stats update failed: %s' % err)
  49             exit(1)
  50     schemes = kdamonds.kdamonds[0].contexts[0].schemes
  51     nr_tried_stats = [s.stats.nr_tried for s in schemes]
  52     if nr_tried_stats[0] == 0 or nr_tried_stats[1] == 0:
  53         print('scheme(s) are not tried')
  54         exit(1)
  55
  56     # Because the second scheme was having the apply interval that is ten times
  57     # lower than that of the first scheme, the second scheme should be tried
  58     # about ten times more frequently than the first scheme.  For possible
  59     # timing errors, check if it was at least nine times more freuqnetly tried.
  60     ratio = nr_tried_stats[1] / nr_tried_stats[0]
  61     if ratio < 9:
  62         print('%d / %d = %f (< 9)' %
  63               (nr_tried_stats[1], nr_tried_stats[0], ratio))
  64         exit(1)
  65
  66 if __name__ == '__main__':
  67     main()