How to disable/limit pixmap cache in X

Glynn Clements glynn at
Thu Sep 20 01:41:53 PDT 2007

Carsten Haitzler (The Rasterman) wrote:

> > The problem in the thin client world is that when an app runs wild with
> > pixmaps it is possible to chew up all available RAM.  This in turn hard
> > freezes thin clients.
> X has a command-line option for this. Several actually:
> -ld int                limit data space to N Kb
> -lf int                limit number of open files to N
> -ls int                limit stack space to N Kb
> note this limits data allocation as a whole - so not just pixmaps (which is
> what you want really as other data does take space - windows, GC's etc. too). i
> would repeat what others have said. doing this can and will impact apps.
> either they will crash or just behave totally strangely - very few, if any
> actually catch x errors and then trace the error (as it's async) and have a
> code path to deal with running out of resources. it's just too much work.

AFAICT, the above just translate into a setrlimit() for the X server
process; if that's the case, it would just kill the X server if the
limits are exceeded.

Glynn Clements <glynn at>

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