Petsc Error

Barry Smith bsmith at mcs.anl.gov
Tue Oct 9 11:59:32 CDT 2007


  On most OS's just because you have greater than a certain amount of
physical memory does not mean that a SINGLE process can utilize it.
For example, many times a single process is limited to 2, 3 or 4 gigabytes.
This is EVEN with 64 bit pointers (and certainly with 32 bit).

   Barry

Run a simple C program that mallocs a chunk of memory. How much you 
you malloc?

On Tue, 9 Oct 2007, Berend van Wachem wrote:

> Hi,
> 
> I ran the same command again, running top, and got the result
> 
> Mem:   6220940k total,  5879056k used,   341884k free,   143992k buffers
> Swap:  1951888k total,     2584k used,  1949304k free,  2363516k cached
> 
>   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
> 19117 berend    25   0 3037m 2.5g 3508 R  100 41.4   0:44.96 MultiFlow
> 
> 
> 
> just before it crashed. I have a 2 processor machine with total 6 GB of memory
> (2 times 3 gb?), so I don't think it should be out of memory. How can I verify
> this for sure?
> 
> Thanks,
> 
> Berend.
> 
> 
> 
> Matthew Knepley wrote:
> > On 10/9/07, Berend van Wachem <berend at chalmers.se> wrote:
> > > Hi,
> > > 
> > > On the command
> > > 
> > >   ierr = DACreateLocalVector(da,g); CHKERRQ(ierr);
> > > 
> > > I get the error
> > > 
> > > 
> > > [0]PETSC ERROR: PetscMallocAlign() line 61 in src/sys/memory/mal.c
> > > Memory requested 6050600
> > > [0]PETSC ERROR: PETSC: Attaching gdb to Debug/MultiFlow of pid 19087 on
> > > display :0.0 on machine tfdpc102
> > > 
> > > 
> > > What does it mean exactly? Out of memory?
> > 
> > Yes. This is strange. The line above these two should read "Out of memory".
> > 
> >   Matt
> > 
> > > Thanks,
> > > Berend.
> > > 
> > > 
> > 
> > 
> 
> 




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