On Fri, Feb 27, 2009 at 6:08 PM, Danny Baumann <dannybaum...@web.de> wrote:
> Hi,
>
>> compiz++ version of scale where if scale was initiated with more than
>> 10 windows, compiz would go into an infinite loop, using 99% CPU and
>> requiring that the user puts their system in single-user mode to get
>> rid of compiz.
>>
>> I have tracked down the bug to a problem in findBestSlots () function
>> in PrivateScaleScreen where the line 'if (d0 + d < sw->priv->distance)
>> ...' meant that some windows were never assigned a slot ID number.
>> This in turn meant that fillInWindows would fail to return false
>> because two slots had the same ID number (0). This in turn meant that
>> the 'do { .... } while (priv->fillInWindows ())' would become
>> infinite.
>>
>> In order to fix this, I had to remove that if statement and assign an
>> ID number to all windows that should be scaled. There are no
>> regressions so far and scale appears to work with more than 200
>> windows open. sw->distance has been kept, but I don't see much of a
>> reason for it, other than the compareWindowsDistance function.
>>
>> The patch is attached. Obviously, I would classify it as a workaround
>> as that if statement was probably there for a reason (undocumented
>> however), however if we can't fix this bug it would be a major
>> stability regression once users move to compiz++.
>
> Can you try to track down what happens in the C version of scale in this
> scenario? The code you're talking about exists since quite some time in
> the C version, so something must be different in the C++ version.Sure, I'm not quite so sure about why the code existed in the scale plugin, clearly preventing any window that should be scaled from getting an ID number more than 0 would _always_ through compiz into an infinite loop due to the way fillInWindows works. I guess we can say that this was some kind of disaster waiting to happen... Kind Regards, Sam. > > Regards, > > Danny > _______________________________________________ > Dev mailing list > Dev@lists.compiz-fusion.org > http://lists.compiz-fusion.org/mailman/listinfo/dev > -- Sam Spilsbury _______________________________________________ Dev mailing list Dev@lists.compiz-fusion.org http://lists.compiz-fusion.org/mailman/listinfo/dev
