Comment 0 for bug 565981

Binary package hint: xorg

There has been some buzz the last days about excessive swapping and OOM conditions. It can seem like the kernel memory use is increasing since the user processes seem not to grow unusually.

/sys/kernel/debug/dri/0/gem_objects shows that the GEM object bytes number is increasing. One way to reproduce, is this:

$ for t in `seq 1 10`; do eog /usr/share/backgrounds ; echo `grep "object bytes" /sys/kernel/debug/dri/0/gem_objects` `ps ocomm,vsz,rss 1020|grep X`; done
142376960 object bytes Xorg 25812 15372
145907712 object bytes Xorg 25812 15372
150458368 object bytes Xorg 25812 15372
154816512 object bytes Xorg 25812 15372
159244288 object bytes Xorg 25812 15372
163721216 object bytes Xorg 25812 15372
168148992 object bytes Xorg 25812 15372
172699648 object bytes Xorg 25812 15372
177152000 object bytes Xorg 25812 15372
181530624 object bytes Xorg 25812 15372

It shows that the Xorg process is not growing, but gem objects are. Similarly counting and summing objects show there are gem objects adding up (with refcount 2) but not disappearing again when the application closes:
 awk '/name/{ i++; s+= $4 } END{print i " " s}' /sys/kernel/debug/dri/0/gem_names

These issues have been seen on intel and ati, with the lucid kernel as well as the mainline 2.6.34 snapshot.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: xorg 1:7.5+5ubuntu1
Uname: Linux 2.6.34-999-generic i686
Architecture: i386
Date: Sun Apr 18 15:59:21 2010
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: xorg
system:
 distro: Ubuntu
 codename: lucid
 architecture: i686
 kernel: 2.6.34-999-generic