Something has a memory leak

[Colin Ian King]

I've tracked memory utilisation of maliit-server over a 12 hour period and can see that the heap is growing at about 1700 bytes a second. One can see this by strac'ing the process and seeing glib's malloc performing 4K mprotects every ~2.4 seconds and the occasional 1MB mmap2 to anonymous memory (aka heap) every 600-620 seconds.

[pid 2708] 12:48:57 mprotect(0xa01fa000, 4096, PROT_READ|PROT_WRITE) = 0
[pid 2708] 12:48:59 mprotect(0xa01fb000, 4096, PROT_READ|PROT_WRITE) = 0
[pid 2708] 12:49:02 mprotect(0xa01fc000, 4096, PROT_READ|PROT_WRITE) = 0
[pid 2708] 12:49:04 mprotect(0xa01fd000, 4096, PROT_READ|PROT_WRITE) = 0
[pid 2708] 12:49:07 mprotect(0xa01fe000, 4096, PROT_READ|PROT_WRITE) = 0
[pid 2708] 12:49:09 mprotect(0xa01ff000, 4096, PROT_READ|PROT_WRITE) = 0
[pid 2708] 12:49:11 mmap2(0xa0200000, 1048576, PROT_NONE, MAP_PRIVATE|MAP_ANONY
MOUS|MAP_NORESERVE, -1, 0) = 0xa0200000
[pid 2708] 12:49:11 mprotect(0xa0200000, 135168, PROT_READ|PROT_WRITE) = 0

Over a period of 1 day this will leak 140MB.

[Colin Ian King (colin-king)]

To show the heap growth, run:

smemstat -p $(pidof maliit-server) 10

..and one sees ~1640 bytes per second heap growth.

[Michael Sheldon (michael-sheldon)]

This appears to occur in all graphical applications running on the phone (but not on the desktop). Running "smemstat -p $(pidof unity8-dash) 10" provides the same symptoms. So presumably this is a result of an issue somewhere lower down in the stack. I haven't been able to figure out what specifically, so I'll add any projects that seems plausible and their respective developers can remove/invalidate them as appropriate.

[Daniel d'Andrada (dandrader)]

Are you sure this is not bug 1206146?

[Timo Jyrinki (timo-jyrinki)]

There's also already bug #1364404 "qmlscene is leaking ~1.7K per second on an idle application on the phone".