Re: Memory Leak

[Sergei Steshenko]

--- On Sat, 1/19/13, James Sherman Jr. <address@hidden> wrote:

> From: James Sherman Jr. <address@hidden>
> Subject: Re: Memory Leak
> To: "Sukanta Basu" <address@hidden>
> Cc: address@hidden
> Date: Saturday, January 19, 2013, 9:34 PM
> On Sat, Jan 19, 2013 at 10:46 PM,
> Sukanta Basu <address@hidden>
> wrote:
> > Hi,
> >
> > I am using Octave 3.6.2 on Ubuntu 12.10. I have written
> a code for solving
> > certain fluid dynamics problem (~5000 lines) using
> Octave and the
> > openmpi_ext toolbox. I am noticing a strange problem
> with Octave. The memory
> > usage slowly increases with each iteration. My computer
> has a RAM of 24 GB.
> > Initially, Octave consumes ~3 GB of memory, then the
> consumption goes as
> > high as 24 GB. At this point, the simulation crashes
> with a "bus error". If
> > I restart the simulation, the same thing happens. I
> cannot figure out the
> > cause for this memory leakage. Can anyone help? I have
> found the same
> > problem on multiple machines (all has identical
> hardware/software
> > configurations).
> >
> > Thanks,
> > Sukanta Basu
> >
> > _______________________________________________
> > Help-octave mailing list
> > address@hidden
> > https://mailman.cae.wisc.edu/listinfo/help-octave
> >
> 
> Hi Sukanta,
> 
> Without knowing/seeing your code, its hard to diagnose
> anything
> definitely.  However, I've run into this problem from
> time to time if
> there is a particular matrix/cell array that grows without
> bound.  Or
> possibly if there is a function that uses significant (e.g.
> more than
> linear) memory the larger the input becomes.  Are there
> any variables
> that you keep from iteration to iteration?  Have you
> monitored how
> large they get (if they change size)?  Is there someway
> to stop and
> save the current state at a certain iteration, then restart
> the
> simulation at that point?  If so, how does memory usage
> change, if
> any.
> 
> I don't know how useful this is, but hopefully it will at
> least give
> you a start to diagnosing the problem.
> 
> James Sherman
> _______________________________________________


"Bus error" is a HW error message typically caused by a wrong CPU instruction. 
For example, CPU is ordered to perform a misaligned access.

So, it's not a bug in the OP's code - it's "down" - Octave C++ code, or 
standard libraries, or compiler, etc.

Regards,
  Sergei.