Performance change from X in Fedora Core 4 to Fedora Core 5

Clemens Eisserer linuxhippy at
Thu Jul 13 04:44:53 PDT 2006

> Since nVidia are managing to pipeline to these pixmaps, it is likely
> that the alloc/dealloc process is an illusion. Presumably, they are
> firing the drawing operations somewhere into a permanently allocated
> area of video memory and just making it look like new memory to the
> client side. The GPU has to know where the final rastering is to go
> somewhere before the end of the pipeline and probably needs the info
> right at the start.

Sorry I think  you misunderstood me ;-)
Nobody pipelines anything, nvidia developers just confirmed that
allocation/deallication is a really bad thing and that this is the
reason why so much time is spent inside of malloc and software
rendering routines.
They first allocate a pixmap in RAM and only if its "worth" to put it
into VRAM (first copyarea?) the upload it into vram. However future
nvidia drivers will allow to disable that feature with the result that
a lot of time is spent waiting for the GPU.

Allocation of mb-sized resources can never we a no-brainer...

lg Clemens

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