[MPlayer-users] Segmentation fault in pre5

[D Richard Felker III]

On Sat, Oct 16, 2004 at 11:45:35PM +0100, Martin Simmons wrote:
> >>>>> On Sat, 16 Oct 2004 18:06:50 -0400, D Richard Felker III <dalias at aerifal.cx> said:
> > On Sat, Oct 16, 2004 at 08:33:26PM +0200, Stefan Sassenberg wrote:
> > > On Fri, Oct 15, 2004 at 07:19:32PM -0700, Corey Hickey wrote:
> > > > Stefan Sassenberg wrote:
> > > > > Hello,
> > > > > 
> > > > > I frequently have segmentation faults when mencoding a movie.
> > > > > Unfortunately this happens at different positions. I can provide some
> > > > > information about this problem. I should add that I had other problems
> > > > > of similar kind that I only solved by rebuilding mencoder with
> > > > > ./configure --disable-mmx2 which I'm currently using.
> > > > > 
> > > > 
> > > > Are you saying that it happens at a different position each time you try
> > > > the same command on the same file? If so, then you probably have
> > > > unstable hardware. I've found that mencoder is very intolerant of
> > > > overclocking, probably from a combination of working the CPU very hard
> > > > and the time it takes to encode.
> > > > 
> > > > If you are overclocking, try overclocking a little less; or, try cooling
> > > > your CPU better.
> > > > 
> > > Correct. Just like the other problem I once had that I mentioned above.
> > > I also thought about hardware problems, but mencoder is the only application
> > > that shows errors like these and I'm not overclocking. Heat problems
> > > might be the cause anyway.
> > 
> > anything that happens at a random location each time you run a program
> > is _definitely_ heat-caused. mencoder doesn't read from /dev/urandom
> > and pick what to do based on the results. the results of each run are
> > entirely deterministic and won't vary from one to another.
> 
> There is plenty of other non deterministic problems that are not caused by
> heat or urandom.  Particular cases that I've seen (not in mencoder yet):
> 
> - timing-related issues for interaction between threads or processes

not threaded. this is one reason threaded apps suck.

> - hardware bugs (CPUs with broken borderline cases in the MMU)

ok, there can be other hardware problems than heat. it's still a
hardware problem.

> - OS bugs (causing registers to be corrupted)

never seen this myself...maybe windows? :o

rich