[gmx-users] Re: genbox Not enough memory

[Jochen Hub]

Hi,

this is due to the way genbox -ci is currently implemented. It calles 
add_conf() too often which leaks memory. So you'll have to edit the code.

Jochen


You'll have to edit the genbox code in order

Am 10/10/12 7:14 PM, schrieb Dr. Vitaly Chaban:
>>
>> Thanks..You are right...The last line of gro file says 250 so it is in nm!...
>>
>> On 10 October 2012 12:30, Christopher Neale
>> <chris.neale at mail.utoronto.ca> wrote:
>>> Sounds like you ran out of memory. Many clusters have a few large-memory nodes. Can you use one of those?
>>> It's failing on a call for 1.3 Gb of memory, which by itself isn't really a lot...
>>>
>>> Also, can you confirm 250 A box length, not 250 nm box length? Gromacs defines length in units of nm.
>>>
>>> Chris.
>>>
>>> -- original message --
>>>
>>> I am trying to build a polymer in solvent system by solvating my fully
>>> extended polymer chains in a box of size 250 250 250 A. I am adding
>>> 4500 solvent molecules as below
>>>
>>>   genbox -cp Solute.gro -ci solvent.gro -o solvated.gro -nmol 4500
>>>
>>> Adding solvents is a slow process and takes much time and at the end I get:
>>>
>>> Program genbox, VERSION 4.5.4
>>> Source code file: smalloc.c, line: 214
>>>
>>> Fatal error:
>>> Not enough memory. Failed to realloc 1338273212 bytes for grid->nra,
>>> grid->nra=0x0
>>> (called from file nsgrid.c, line 483)
>>> For more information and tips for troubleshooting, please check the GROMACS
>>> website at http://www.gromacs.org/Documentation/Errors
>>>
>>> Is this happening because of the huge amount of free space to be
>>> filled with the solvent? Please help me.
>
>
> Genbox sometimes suffers from the out-of-memory error. Based on my own
> investigation, this is indeed what happens here, because the utility
> uses a kind of grid during its operation. The larger the cell, the
> more hungry it becomes, no matter how many molecules you want to
> insert. The standard advice therefore applies - add memory...
>
> Another question is why you need such a huge box? The only thing I
> could imaging is simulating a droplet-vapor/air interface...
>
> Another advice is to start with a smaller box and then extend its
> deminsions using editconf (which does not "care about the box size").
>
>
> Dr. Vitaly V. Chaban
> MEMPHYS - Center for Biomembrane Physics
> Department of Physics, Chemistry and Pharmacy
> University of Southern Denmark
> Campusvej 55, 5230 Odense M, Denmark
>

-- 
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Dr. Jochen Hub
Computational Molecular Biophysics Group
Institute for Microbiology and Genetics
Georg-August-University of Göttingen
Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany.
Phone: +49-551-39-14189
http://cmb.bio.uni-goettingen.de/
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