Re: gEDA-user: PCB is extremely slow

[Randall Nortman <geda-lists@xxxxxxxxxxxxxxx>]

> >>I am editing Ronja Twister
> >>http://ronja.twibright.com/schematics/twister.pcb
> >>And it sometimes takes 30 seconds to redraw (during which PCB doesn't
> >>react). My machine has 1500MHz CPU and 0.5GB of RAM and nothing
> >>CPU intensive is running there besides.

I noticed, after upgrading from an older non-GTK version to a CVS
snapshot from several weeks ago (using GTK+), that sometimes PCB gets
into a funny state where redraws are impossibly slow, as you describe.
After some experimentation I determined that this is influenced by
*other windows* being open on the same desktop, in particular other
maximized windows.  In my case, gschem and acroread were the common
culprits, but I don't know if the phenomenon is limited to them.  It
may be a quirk of my window manager (xfwm4).  I can't reliably
reproduce it, but when it happens, I can fix it by closing other
windows until the problem goes away.  You might think it's a system
memory problem, but I am not swapping when this happens.  PCB will
briefly consume 100% of CPU during any redraws, but otherwise the CPU
is mostly idle.  Since I can't reproduce it on demand, I didn't think
it was worth filing a bug report, but if others are experiencing the
same problem, perhaps it is worth tracking down.

My system is an x86_64 (Athlon64 3000) with 1GB SDRAM running
up-to-date Gentoo in 64-bit mode and xfce4/xfwm4.  One thing just
occurred to me -- I run both gschem and acroread under a 32-bit chroot
environment, since I can't get them to run in 64-bit mode.  This could
have something to do with my problem.

Randall