[OpenIndiana-discuss] X11 memory use

[Alan Coopersmith]

On 12/ 9/13 10:25 AM, Reginald Beardsley wrote:
> FWIW X was a memory hog even 20 years ago.  I suspect much of the memory consumption now is the tables of function pointers needed to implement objects.  As the class structures get more elaborate, the memory consumed grows at an astonishing rate.

You must be thinking of C++ software in X clients, not the X server, which
is plain C and has only a few k of function pointers.

I suspect a much more significant contributor to memory consumption is
simply increased requirements - a 32-bit 1920x1200 screen takes over 90
times the RAM to store the screen image that a 1-bit 1024x768 screen did
20 years ago.

Additionally, now instead of just xterms with a few hundred line scrollback
buffer, you've got webbrowsers with hundreds of icons & images, which get
stored in the X server memory to speed access time when you switch windows
or tabs or pages.

Also remember to run pmap on the X server process and compare the heap size
to the device mappings - counting the VRAM mapping of a 1gb video card
against the X memory usage gives you a poor idea of actual RAM usage.

-- 
	-Alan Coopersmith-              alan.coopersmith at oracle.com
	 Oracle Solaris Engineering - http://blogs.oracle.com/alanc