No meu caso, está ocupando quase 50% da memória disponível.
Amigão, entre com o comando top no terminal e poste aqui oq retorna.
Abaixo está o 'top'
top - 22:12:07 up 17 min, 2 users, load average: 0.97, 1.25, 0.92
Tasks: 116 total, 2 running, 114 sleeping, 0 stopped, 0 zombie
Cpu(s): 30.8%us, 1.3%sy, 0.0%ni, 67.9%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1028588k total, 928080k used, 100508k free, 16068k buffers
Swap: 3012148k total, 0k used, 3012148k free, 415688k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
6863 aff 20 0 526m 43m 17m S 10.7 4.4 1:00.60 totem
5804 root 20 0 153m 39m 10m S 9.3 4.0 0:33.34 Xorg
6122 aff 20 0 146m 6624 3864 S 3.3 0.6 0:12.96 pulseaudio
6213 aff 20 0 253m 34m 11m S 2.7 3.4 0:31.14 compiz.real
6922 aff 20 0 211m 24m 14m S 1.3 2.4 0:02.16 gnome-system-mo
6928 aff 20 0 259m 28m 11m R 1.3 2.8 0:01.00 gnome-terminal
6108 aff 20 0 251m 12m 9228 S 0.7 1.2 0:00.71 gnome-settings-
1 root 20 0 4016 876 592 S 0.0 0.1 0:00.82 init
2 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kthreadd
3 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/0
4 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/0
5 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/0
6 root 15 -5 0 0 0 S 0.0 0.0 0:00.02 events/0
7 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 khelper
40 root 15 -5 0 0 0 S 0.0 0.0 0:00.06 kblockd/0
43 root 15 -5 0 0 0 S 0.0 0.0 0:00.06 kacpid
44 root 15 -5 0 0 0 S 0.0 0.0 0:00.08 kacpi_notify
147 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kseriod
192 root 20 0 0 0 0 S 0.0 0.0 0:00.04 pdflush
193 root 20 0 0 0 0 S 0.0 0.0 0:00.00 pdflush
194 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kswapd0
238 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 aio/0
1597 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 ksuspend_usbd
1600 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 khubd
1612 root 15 -5 0 0 0 S 0.0 0.0 0:00.06 ata/0
1618 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 ata_aux
1625 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 khpsbpkt
2364 root 15 -5 0 0 0 S 0.0 0.0 0:00.10 scsi_eh_0
2370 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 scsi_eh_1
2374 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 knodemgrd_0
2397 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 scsi_eh_2
2399 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 scsi_eh_3
2597 root 15 -5 0 0 0 S 0.0 0.0 0:00.20 kjournald
2892 root 16 -4 17156 1276 384 S 0.0 0.1 0:00.36 udevd