Hah. Funny, I posted somehow related thread on memory consumption a way back (don't have the time to look it up). The reply I got was "linux uses all the available memory by default". I also noticed phone lagging VERY much once RAM is 100% full (and swap is necessary). This makes sense as flash is slow(seems to be especially slow on N9 but that is my own opinion).
~ # for i in {1 2 3}; do hdparm -tT /dev/mmcblk0 2>/dev/null; done /dev/mmcblk0: Timing buffer-cache reads: 280 MB in 0.51 seconds = 561679 kB/s Timing buffered disk reads: 94 MB in 3.00 seconds = 32071 kB/s /dev/mmcblk0: Timing buffer-cache reads: 280 MB in 0.50 seconds = 562285 kB/s Timing buffered disk reads: 95 MB in 3.02 seconds = 32176 kB/s /dev/mmcblk0: Timing buffer-cache reads: 302 MB in 0.51 seconds = 604549 kB/s Timing buffered disk reads: 95 MB in 3.02 seconds = 32137 kB/s
~ # for i in {1 2 3}; do hdparm -tT /dev/mmcblk0 2>/dev/null; done /dev/mmcblk0: Timing buffer-cache reads: 138 MB in 0.51 seconds = 276993 kB/s Timing buffered disk reads: 80 MB in 3.00 seconds = 27297 kB/s /dev/mmcblk0: Timing buffer-cache reads: 144 MB in 0.51 seconds = 288364 kB/s Timing buffered disk reads: 79 MB in 3.02 seconds = 26757 kB/s /dev/mmcblk0: Timing buffer-cache reads: 152 MB in 0.51 seconds = 305113 kB/s Timing buffered disk reads: 81 MB in 3.01 seconds = 27466 kB/s