[CPMD-list] Memory problems on 2GB P4- unable to allocate >1GB memory

[Justin Toh]

Hello,

I run cpmd on a P4 machine with 2GB of RAM. The OS is redhat 4.2.19.

I'm having a problem running jobs larger than 960 MB in size. Above this
limit, the following sorts of error messages appear:
-------------------------------------------------------------------
 GENERATE ATOMIC BASIS SET
     Pt        PSEUDO ATOMIC ORBITALS
        L VALUE=S                      OCCUPATION= 1.00
[....]

 PROCESSOR     0 ALLOCATION OF    21901544 WORDS OF MEMORY FAILED
 ****************************************************************

 ***    MEMORY| THE NEW SIZE OF THE PROGRAM IS  163608 kBYTES ***

 ================================================================
                      BIG MEMORY ALLOCATIONS
 C0             109507688                CM              21901544
 TWNL            11407050                SCR              7097615
 XF               1929098                DQG              1929098
 YF               1929098                HGKP             1013945
 HGKM             1013945                VPS               608367
 ----------------------------------------------------------------
 [PEAK NUMBER   56]      PEAK MEMORY    153768836 = 1230.2 MBytes
 ================================================================


 PROGRAM STOPS IN SUBROUTINE MEMORY| ALLOCATION FAILED (C2)


--------------------------------------------------------------------~

limit settings are:
cputime 	unlimited
filesize 	unlimited
datasize 	unlimited
stacksize 	8192 kbytes
coredumpsize 	0 kbytes
memoryuse 	unlimited
descriptors 	1024
memorylocked 	unlimited
maxproc 	3072
openfiles 	1024

The flags and options are:
FFLAGS =  -w90 -w95
LFLAGS = -L${MKL_LIB} -lmkl_lapack -lmkl_p4 -lpthread -lguide -Vaxlib
$(QMMM_LIBS)
CFLAGS =
CPP = /lib/cpp -P -C -traditional
CPPFLAGS = -D__Linux -D__PGI -DLAPACK -DFFT_DEFAULT -DLINUX_IFC
CC = gcc -O2 -Wall
FC = ifc -c -O3 -tp p6 -axiM
LD = ifc -O3 -tp p6 -axiM
AR =

Actually, this is problem is common to Fortran programs on the system- a
simple fortran matrix-matrix mutiplication routine crashes at the 960 MB
mark,
whereas a c-program can allocate 1.5 GB easily.

We've played around with the kernel (although the fact that allocation
works in c makes me think that this isn't the problem).

Has anyone else encountered this problem? Any suggestions would be greatly
appreciated.

Cheers,
Justin


Justin Toh

Mob: 07970 657027               Lab: +44 (01223) 336350
Trinity College			Department of Chemistry
Cambridge UK			Lensfield Road
CB2 1TQ