Xorg: xserver using _a lot_ memory

[Pete Zaitcev]

On Fri, 16 Jan 2009 14:10:06 +0100, Christoph Höger <choeger at cs.tu-berlin.de> wrote:

> 16840 root      20   0  577m 250m  11m S  3.7 12.6  22:10.17 Xorg
> So where did my memory go? And who of you guys has it? I want it back ;)

On my box it looks like this:
 3115 root      20   0  466m  43m  10m S  0.3  2.3   1:18.40 Xorg

A quick look at /proc/3115/maps shows that only 32MB of this
is used to map the framebuffer (I have a Radeon, DRI is active).

The biggest chunk, 270MB, is used to map shared libraries.
We sure have a lot of useless code and rodata in there. For example,
libdbus uses 2.3MB. Seriously, DBus? Then we have XML parser, etc.
Even libpciaccess uses 2MB! For comparison, the whole of libc fits
into 1.5MB.

Second biggest chunk, 55MB, is the heap, which is what librestop shows.
The framebuffer is only the third.

Among the three of them, the above cover 357MB or 87% of the virtual
memory. The rest is gone to small things like DRI, X modules, SYSV IPC,
and process stacks.

My TLB is crying for mercy trying to cover all that.

-- Pete