summary of large rwf spliting



Dear CCL Members:
 According your advice, I have solved the large rwf spling problem.
 ere is my adding line.
 %RWF=f1,2000MB,f2,2000MB,f3,2000MB
 or
 %RWF=f1,240MW,f2,240MW,f3,240MW
 the default path is the current directory.
 You may give the path, such as
 %RWF=/home/lboc/tmp1/f1,2000MB,/home/lboc/tmp2/f2,2000MB
 Here is the summary. thanks to everyone.
 THE original problem is:
     I use Gaussian A.7 to do MP2 frequency calculation.My workstation's
 configuration is 30G hard disk and 780M memory. However,when I calculate
 a system with 7 heavy atoms using MP2/6-31+g**, The calcualtion will stop
 with the following message:
 Erroneous write during file extend. write 114687 instead of 4096
 Probably out of disk space.
 I have split the scratch file as the following:
       %rwf=f1,2GB,f2,2GB
 However,the calculation still stop after the first file(f1) exceed 2.1G,while
 f2 do not contain any data. Does anyone have the similar experience and how
 to deal with the problem?
 Thanks a lot!
 Yours
 -----------------------------
 REPLY from Matthias is:
 in former versions of Gaussian, the memory limit in the %rwf line
 _must_ be in words. I'm not sure about G98 Rel.A7.
 I also used in all cases slightly less than 2 GB for each file,
 as example:
 %RWF=/scratch/f1.rwf,200000000,/scratch/f2.rwf,230000000,/scratch/f3.rwf,-1
 Maybe this helps.
 Matthias
 ------------------------------
 REPLY from Paul is:
 I had this pb some times. It seemed to me that it was a file system
 limitation : they must not
 exceed 2GB.... but with G98, I discovered that most of the times, I had to put
 the limit well below, around
 1.5GB or 1.6GB.
   Hope this helps,
 Paul.
 Fleurat-Lessard Paul                        | fleurat { *at * }
 lpct.u-bordeaux.fr
 Laboratoire de Physico Chimie Moleculaire,  | Phone: (33)(0)5 56 84 63 09
 Universite Bordeaux I, 33400 Talence, FRANCE| Fax : (33)(0) 5 56 84 66 45
 ------------------------------
 REPLY from Roy is:
 You may need to add a decimal point to the numbers. I had problems with 2
 and 2.0GB rwf files. Try makin the rwf files 1.8GB.
 Roy Jensen
 -------------------------
 REPLY from Tapas is:
 Check the limit of filesize using command "limit"  (in AIX), ulimit
 (TrueUnix).
 Change it to unlimited.
 Tapas Kar, Ph. D
 Department of Chemistry & Biochemistry
 Utah State University
 Logan, UT 84322-0300
 Tel: 435-797-7230
 Fax: 435-797-3390
 Email: tapaskar { *at * } cc.usu.edu
        tapas { *at * } risky3.chem.usu.edu
 ---------------------------
 REPLY from Cust. is:
 While formally files up to 2GB can be used there is overhead which is
 makes some of this unavailable.  I find that 240MW is safe for all calculations
 so
 %rwf=f1,240mw,f2,240mw
 #  ... MaxDisk=480mw
 should get you past the 2GB limit.
   Note that MP2 frequencies cannot restrict things to the MaxDisk limit
 but you will get a note on the smallest disk required. I suspect for this
 case that two files will be sufficient but you should consider defining
 more to be on the safe side since you have enough.  The maximum is 8 files
 for about 16GB and if you shorten the file names to a single character
 you will be able to fit it all on one 80 character line.
 -----------------
 REPLY from Prof.Curt is
 Have you tried the Gaussian route card option MP2=semidirect?  I think
 you need to reduce your scratch / rwf usage to get around these
 limitations.  You may also have run up against an old OS limitation on
 file size.
 Curt Breneman
 RPI Chemistry
 ---------------------
 REPLY from Pedro is
 Hi
 try SCF=Direct Maxdisk=4200Mb or the maximum available
 hope it helps
  Pedro Salvador Sedano             |
  Ph.D. Student                     | I'll stare the sundown
  Institut de Quimica Computacional |  until my eyes go blind...
  Universitat de Girona             |  I won't change direction
  Campus Montilivi 17071            |   and I won't change my mind.
  Girona  Spain                     |
  e-mail: perico { *at * } stark.udg.es       |
  WWW: http://stark.udg.es/~perico  |
  Telf: +34 972 418358              |
 ---------------------
 REPLY from Thomas is
 splitting th rw-file is probably without any success unless you have
 some restrictions concerning the maximum filesize at your system. First
 you should try the option: MP2(VeryStingy) and have a look if using
 MP2(FullDirect) works. Then there are some other possible problems. See
 if the MaxDisk-option in the Default.Route file is set. If you do not
 find a Default.Route file then there are no MaxDisk restrictions. But as
 far as my experience goes to allocate 4GB for the rw-file is very often
 insufficient. If you can try %rwf=f1,20GB. Last but not least you should
 see what's the size of your f1 and f2 at the error termination of your
 job. If both are 2GB then you need to allocate more disk space otherwise
 there is another problem.
 Hope could help you
 --------------
 REPLY from Borislav is
 I think you should try with %rwf=f1,240MW,f2,240MW.
                                     Boris
 ===========================================================================
   Boris Kovacevic                       Phone: (385) (1) 4561-117
   Quantum chemistry group               Fax:   (385) (1) 4561-118
   Institut Rudjer Boskovic              e-mail: boris { *at * } spider.irb.hr
   Bijenicka 54, 10000 Zagreb            http:
   Croatia
 ----------------
 REPLY from Thomas is
 sorry I did not read the last sentences of your mail. I know this
 problem. First try
 %rwf=f1,2GB,f2,2GB,
 The last comma is important! If that doesn't work try
 %rwf=f1,230MW,f2,2GB,
 But why do you split your rw-file and why don't you allocate
 %rwf=f1,2GB  ???
 Please tell me if you have any success.
 Greetings
 Thomas
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