Bill Crawford billcrawford1970 at
Thu Apr 9 02:20:43 PDT 2009

On Wednesday 08 April 2009 21:28:47 Alan Cox wrote:

> Backing store has long been off by default in Xfree/Xorg. Fundamentally
> its a dumb design issue in the concept of backing store - it means the
> server has to consume huge amounts of memory keeping copies of stuff and
> if someone massively resizes a window with backing store (remembering it
> can be mostly offscreen) your X server explodes.

Remind us why turning it on for all windows all the time (Composite) is better 
than for one window? ;o)

> Backing store was mostly a mistake at the time of introduction (as
> opposed to save unders which are a least reasonably resource bounded).

It was overused, sure, but the idea suggested elsewhere in the thread of using a 
pixmap and setting that as the window background is essentially doing the same 
thing (a form of double buffering).

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