Comment 3 for bug 1888558

Hi folks, an update on my VLC measurement. I finally did that "vlc -vvv", please see attachments for the stderr. I don't see anything interesting there. But I did make snapshots of the vsize, rss, and the "smaps" file under the /procfs/$PID/smaps --they are also attached. I played the same video for less than 12 minutes then paused it. Then let the window sit there like what I did before. The observation covered for about 20 hours total.

The file "vlc-vvv-usage-wirawan2-Sisters_M16.txt" contains the output of "ps faux" commands taken over regular interval (timestamp shown as cols 1-2) for this one process.

I plotted the vsize and rss from that ps output file (using pandas, in case you're curious), I did see linear growth in the memory usage in several stretches of time. And these stretches did not grow with the same rate. I omitted the first line of the measurement because it is not relevant (vlc was being started).

The smap files are timestamped with the UNIX time and the date/time--the meaning should be clear from the filename. I supplied you three snapshots:

* `smaps-1596468720-20200803T113241.txt`: about 5 minutes into the video playing (still running)
* `smaps-1596510832-20200803T231352.txt`: about 12 hours later (video paused)
* `smaps-1596540657-20200804T073057.txt`: about 20 hours later (video paused)

I did see some new memory regions allocated and it was not clear what they are. But that's all the clue I could gather from my testings. Hope all these help pinpointing the cause of the memory leak.

Here is an example analysis:

~~~
$ diff -y --width=200 <(grep -e '^[0-9a-f]+-[0-9a-f]+' -e 'Dirty' -e Rss smaps-1596468720-20200803T113241.txt) <(grep -e '^[0-9a-f]+-[0-9a-f]+' -e 'Dirty' -e Rss smaps-1596510832-20200803T231352.txt) |less
...

7fc19ec74000-7fc19ed74000 rw-s 00000000 00:1a 264 /i915 (deleted) | 7fc188000000-7fc18b61a000 rw-p 00000000 00:00 0
Rss: 404 kB | Rss: 55400 kB
Shared_Dirty: 0 kB Shared_Dirty: 0 kB
Private_Dirty: 404 kB | Private_Dirty: 55400 kB
7fc19ed74000-7fc19ed88000 rw-s 00000000 00:1a 802 /i915 (deleted) | 7fc18b61a000-7fc18c000000 ---p 00000000 00:00 0
Rss: 4 kB | Rss: 0 kB
Shared_Dirty: 0 kB Shared_Dirty: 0 kB
Private_Dirty: 4 kB | Private_Dirty: 0 kB
                                                                                                   > 7fc190000000-7fc198000000 rw-p 00000000 00:00 0
                                                                                                   > Rss: 131072 kB
                                                                                                   > Shared_Dirty: 0 kB
                                                                                                   > Private_Dirty: 131072 kB
                                                                                                   > 7fc198000000-7fc19c000000 rw-p 00000000 00:00 0
                                                                                                   > Rss: 65536 kB
                                                                                                   > Shared_Dirty: 0 kB
                                                                                                   > Private_Dirty: 65536 kB
                                                                                                   > 7fc19ec88000-7fc19ed88000 rw-s 00000000 00:1a 243 /i915 (deleted)
                                                                                                   > Rss: 716 kB
                                                                                                   > Shared_Dirty: 0 kB
                                                                                                   > Private_Dirty: 716 kB
7fc19ed88000-7fc19ed90000 rw-s 00000000 00:1a 799 /i915 (deleted) 7fc19ed88000-7fc19ed90000 rw-s 00000000 00:1a 799 /i915 (deleted)
Rss: 32 kB Rss: 32 kB
Shared_Dirty: 0 kB Shared_Dirty: 0 kB
Private_Dirty: 32 kB Private_Dirty: 32 kB
~~~

Left column is the 5-minute smaps, and the right column is the 12-hour smaps.

Wirawan