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Re: "No more memory available" -- a recurring problem
*To*: mathgroup at smc.vnet.net
*Subject*: [mg68388] Re: [mg68356] "No more memory available" -- a recurring problem
*From*: János <janos.lobb at yale.edu>
*Date*: Thu, 3 Aug 2006 06:07:20 -0400 (EDT)
*References*: <200608020924.FAA28575@smc.vnet.net> <D6C89613-F0EB-4D7E-9E29-2FFAA6FB40D4@yale.edu> <321730f50608021216o11d69435g5d278a6b7d06dfa5@mail.gmail.com>
*Sender*: owner-wri-mathgroup at wolfram.com
Charlie,
Your MacBook Pro has an Intel core duo processor and looks to me
that Mathematica is using just one of the cores. I do not know what
You can do about it. Probably nothing. If you can put your hand on
a Personal Grid edition that would engage the second core more
vigorously.
I do not see that you have a memory problem as regarding the usage of
the memory reported by top.
You might have a bad memory chip and that is crashing your
program. Unfortunately we see bad memory coming even from Apple
these days with newer Macs. There is a service CD that came with
your MacBook Pro. Try to run the memory test from it all night in a
loop and see if it is caching anything.
You might also want to do a hard drive check with Diskwarrior. Wooly
disks can lead to wooly virtual memory and causing crashes.
Look if you have anything in ~/Library/Logs/Crashreporter regarding
Mathematica.crash.log or Mathkernel.cash.log. /I have plenty in
mine for both :)/ If you find any, send them to support at wolfram.com
and ask their opinion.
I also recommend to do additional exhausting tests for the
motherboard and other elements of the machine by using the service CD.
In summary it looks like a hardware problem - unless you have other
long running Mathematica programs which run just fine.
With the best,
János
On Aug 2, 2006, at 3:16 PM, Charlie Brummitt wrote:
> János,
>
> Thanks for the advice. I'm not really sure how to interpret the
> information in the terminal window, so I have attached screenshots of
> it at various stages (see the names of the images). I have attached
> them in chronological order.
>
> It seems to me that Mathematica is only being allocated 50% of the CPU
> and 100 megabytes of RAM! When I did the "top" on my 12" PowerBook,
> 93% of the CPU was being used while Mathematica was running my code.
> How do I change this on my 15" MacBook Pro?
>
> My 12" PowerBook is able to run this code overnight and very rarely
> gives the "ran out of memory" error message. I would like to be able
> to run my code overnight on my MacBook Pro, but it can only run for 5
> to 10 minutes before it runs out of memory and completely halts. Thus
> I can't "set it and leave it"; instead, I must always be at my
> computer to restart the calculation every 5 to 10 minutes. Any
> suggestions?
>
>
> Thanks for all your help, János.
>
> Charlie
>
> On 8/2/06, János <janos.lobb at yale.edu> wrote:
>>
>> On Aug 2, 2006, at 5:24 AM, Charlie Brummitt wrote:
>>
>> > I keep getting the following error message while running a search
>> > of many PDE's:
>> >
>> > "No more memory available.
>> > Mathematica kernel has shut down.
>> > Try quitting other applications and then retry."
>> >
>> > This message is becoming so common that it is crippling my research
>> > project, which is to find the simplest PDE with one quadratic
>> > nonlinearity that is chaotic.
>> >
>> > I have Googled and searched the Mathgroup archives for help, and I
>> > employed the following fixes:
>> >
>> > --CODE & SOFTWARE--
>> > 1) Share[] -- does not help because my code rarely has common
>> elements
>> > that Share[] could consolidate.
>> >
>> > 2) I used Module[] and made as many variables local as possible. I
>> > eliminated extra variables and functions in addition to adding
>> Clear[]
>> > in several places in the code to clear variables that are no longer
>> > needed.
>> >
>> > 3) I streamlined and optimized the code in general, and I made the
>> > routines as simple and least data-intensive as possible.
>> >
>> > 4) I never have any other applications open when running
>> Mathematica.
>> > (Unfortunately, closing other applications is the only
>> suggestion that
>> > Mathematica provides in the "out of memory" error message.)
>> >
>> > 5) I should note that I run the latest version of Mathematica
>> > (5.2.2.0).
>> >
>> > --HARDWARE--
>> > 1) I upgraded from a 12" PowerBook to a 15" MacBook Pro. This
>> computer
>> > has an 2.16 GHz Intel Core Duo processor.
>> >
>> > 2) I upgraded the RAM on this new computer from 1 GB to 2 GB.
>> >
>> > 3) I now have much more free hard drive space (20 GB) in case
>> > Mathematica needs to use virtual memory. In addition, this hard
>> drive
>> > is 7200 rpm versus the standard 5400 rpm.
>> >
>> >
>> > I have been using functions like MemoryInUse[] and On
>> [MemoryConserve]
>> > to monitor the use of memory. I almost always find that I am only
>> > using a few megabytes at a time (usually 5-10 MB, sometimes as
>> high as
>> > 100 or once 1000 after a large computation). However, despite
>> finding
>> > that I usually use only a few megabytes during my computations, I
>> > often get the above "out of memory" error message, and I can never
>> > figure out why and how much memory was needed in that particular
>> > computation.
>> >
>> >
>> > Some questions:
>> > 1) How can I tell whether Mathematica is using virtual memory or
>> not?
>> > It seems to me that it is not. I have 20 GB of hard drive space
>> free
>> > and it never seems to use it. Why should I ever run out of
>> memory if I
>> > have 20 GB free in case it needs more memory than my RAM provides?
>> >
>> > 2) Is there a way to determine how much of my 2 GB of RAM are
>> > allocated to Mathematica? Can I increase how much RAM
>> Mathematica can
>> > access?
>> >
>> > Thanks in advance for any help you may be able to provide! I
>> greatly
>> > appreciate it. If you need more information on my code or the
>> > computations I am doing, I would be happy to provide it.
>> >
>> > Regards,
>> > Charlie
>>
>> If you open a Terminal window on the side and type "top" and hit
>> return and start up your application, what do You see for real memory
>> usage for the kernel and the front end from top?
>>
>> János
>> <before mathematica.jpeg>
>> <mma loaded, code loaded, pre-execution.jpeg>
>> <running1.jpeg>
>> <running2.jpeg>
>> <running3.jpeg>
>> <running4.jpeg>
>> <ran out of memory.jpeg>
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