[Bug 51576] Re: rss-glx really slow (only 1-2fps) since recent fglrx driver update

[frogzoo]

Noticed this comment that exactly describes the problem, so I'd say the
fix is known, and probably available upstream. Note: setting
memoryLimit=0 in ~/.xscreensaver as they suggest does not fix the
problem.

From: /usr/share/doc/xscreensaver-gl/README.gl

"If you are having problems with running the GL screenhacs from xscreensaver,
but not from a window, please see
<http://www.jwz.org/xscreensaver/faq.html#gl-mem>, especially if you
are using nVIdia's GL implementation. This has appeared as a SIGSEGV
crash and as a failutre to allocate GL context. In particular:

  1.I upgraded to 3.33, and xscreensaver won't run GL hacks any more (or
    they run slowly), but they work fine from the command line.

    Try editing your .xscreensaver file and changing the memoryLimit
    setting to 0. Version 3.33 introduced the memoryLimit option as a
    precautionary limit to prevent runaway memory use if one of the
    display modes happened to be buggy; it prevents any program launched
    by xscreensaver from allocating more than that much memory. It
    defaults to 50M, which is a lot. However, apparently certain OpenGL
    libraries (notably nVidia) do something strange that makes them appear
    to allocate more than 128M of memory for every OpenGL program!
    Consequently, those programs die on startup because they aren't able
    to allocate memory. On some systems, memoryLimit doesn't cause the GL
    programs to crash, but instead, causes them to run slowly
    (non-accelerated.) Turning off the memory limit should work around
    this."

-- 
rss-glx really slow (only 1-2fps) since recent fglrx driver update 
https://launchpad.net/bugs/51576