Looking close at memory usage

Working with 16Mb of physical memory has underscored the importance of two things: first, lightweight applications, and second, keeping a close eye on what is taking up space.

System monitors such as htop are useful for the second point, although using a monitor to watch memory use defeats the purpose to a small degree; it does, after all, take up space. For a shorter, quicker peek, this little script does a great job. Here’s what the output looks like:

 Private  +   Shared  =  RAM used	Program 

  0.0 KiB +  10.0 KiB =  10.0 KiB	dhcpcd
  0.0 KiB +  11.5 KiB =  11.5 KiB	agetty
  0.0 KiB +  12.0 KiB =  12.0 KiB	udevd
  0.0 KiB +  12.5 KiB =  12.5 KiB	startx
  0.0 KiB +  22.5 KiB =  22.5 KiB	xinit
  0.0 KiB +  37.0 KiB =  37.0 KiB	hnb
  0.0 KiB +  42.0 KiB =  42.0 KiB	mc
  0.0 KiB +  49.0 KiB =  49.0 KiB	vim (2)
  0.0 KiB +  49.5 KiB =  49.5 KiB	musca
  0.0 KiB +  50.5 KiB =  50.5 KiB	charm
 40.0 KiB +  11.5 KiB =  51.5 KiB	init
 96.0 KiB +  43.0 KiB = 139.0 KiB	tty-clock
240.0 KiB +  68.5 KiB = 308.5 KiB	htop
312.0 KiB +  41.5 KiB = 353.5 KiB	alpine
500.0 KiB + 243.0 KiB = 743.0 KiB	bash (4)
736.0 KiB +  51.0 KiB = 787.0 KiB	centerim
768.0 KiB +  77.0 KiB = 845.0 KiB	urxvtd
996.0 KiB +  49.0 KiB =   1.0 MiB	Xorg
---------------------------------
                          4.5 MiB
=================================

 Private  +   Shared  =  RAM used	Program 

I find that interesting mostly because it helps answer a long-standing question, of how it all fits. But it also puts a few things into perspective, like the fact that Musca takes up less space than tty-clock, or that htop and alpine are standing on the same amount of ground, more or less.

On a bigger system the results might be a little more intersting. And now I can take a more critical approach to lightweight versus heavyweight software, with some numbers to back myself up. 😈

P.S.: Thanks to LinuxPlanet for pointing it out. 😉