Hi, I am using 32 bit linux (slackware) on a 64 bit opteron. Would using a 64 bit linux distro help?
Berend. Barry Smith wrote: > Pressure your vendors, be they IBM or Redhat, to provide a 2007 OS instead > of a 2001 OS :-(. > > Barry > > > On Tue, 9 Oct 2007, Berend van Wachem wrote: > >> Hi Barry, >> >> Yes, your hint seems correct; a single process can "only" allocate 3 >> gigabytes >> of memory, even if there is more physical memory present. >> >> Is the only work around to run parallel? >> >> Thanks, >> Berend. >> >> >> Barry Smith wrote: >>> 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. >>>>>> >>>>>> >> >
