Find out how long a process is sleeping in Linux?

Question

Basically I want to have all processes that have been sleeping for more than one hour.

I know that there is etime in ps, but sadly it shows the overall lifetime.

How can this be done under linux (preferably with ps)?

Answer 1

The /proc/pid/sched file contains a metric ton of scheduling data:

$ cat sched
bash (2192, #threads: 1)
---------------------------------------------------------
se.exec_start                      :     294360163.632873
se.vruntime                        :         17694.720927
se.sum_exec_runtime                :          2643.766318
se.statistics.wait_start           :             0.000000
se.statistics.sleep_start          :     294360163.632873
se.statistics.block_start          :             0.000000
se.statistics.sleep_max            :      34689385.720961
se.statistics.block_max            :         11337.665116
se.statistics.exec_max             :             7.657145
se.statistics.slice_max            :             0.550257
se.statistics.wait_max             :             7.464190
se.statistics.wait_sum             :            37.981183
se.statistics.wait_count           :                13774
se.statistics.iowait_sum           :          1556.105204
se.statistics.iowait_count         :                  278
sched_info.bkl_count               :                    0
se.nr_migrations                   :                 2816
se.statistics.nr_migrations_cold   :                    0
se.statistics.nr_failed_migrations_affine:                    0
se.statistics.nr_failed_migrations_running:                  335
se.statistics.nr_failed_migrations_hot:                   14
se.statistics.nr_forced_migrations :                    0
se.statistics.nr_wakeups           :                13471
se.statistics.nr_wakeups_sync      :                 3293
se.statistics.nr_wakeups_migrate   :                 2532
se.statistics.nr_wakeups_local     :                  655
se.statistics.nr_wakeups_remote    :                12816
se.statistics.nr_wakeups_affine    :                   78
se.statistics.nr_wakeups_affine_attempts:                 9452
se.statistics.nr_wakeups_passive   :                    0
se.statistics.nr_wakeups_idle      :                    0
avg_atom                           :             0.196329
avg_per_cpu                        :             0.938837
nr_switches                        :                13466
nr_voluntary_switches              :                13447
nr_involuntary_switches            :                   19
se.load.weight                     :                 1024
policy                             :                    0
prio                               :                  120
clock-delta                        :                   95

I suggest reading through the /proc/*/sched files looking for se.statistics.nr_wakeups or se.statistics.wait_count lines that don't change for an hour. I don't know off-hand which one would give you 'better' results, but try both :) and see which one gives you answers like you expect.