After startup:
VmRSS:	    9932 kB

Repeated reassigns of about 12.5M with Array.new:
VmRSS:	   22144 kB
VmRSS:	   34352 kB
VmRSS:	   34352 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
VmRSS:	   46560 kB
after GC.start:
VmRSS:	   22144 kB

Repeated reassigns of about 12.5M with Gdk::Pixbuf.new:
VmRSS:	   34992 kB
VmRSS:	   47560 kB
VmRSS:	   60128 kB
VmRSS:	   72696 kB
VmRSS:	   85264 kB
VmRSS:	   97832 kB
VmRSS:	  110400 kB
VmRSS:	  122968 kB
VmRSS:	  135536 kB
VmRSS:	  148104 kB
VmRSS:	  160672 kB
VmRSS:	  173240 kB
VmRSS:	  185808 kB
VmRSS:	  198376 kB
VmRSS:	  210944 kB
VmRSS:	  223596 kB
VmRSS:	  236180 kB
VmRSS:	  248748 kB
VmRSS:	  261316 kB
VmRSS:	  273904 kB
after GC.start:
VmRSS:	   22904 kB