Dear Lapack Team,
I have a question concerning internal restrictions according to the
size of the matrices.
I am using SSYEVX and my code works well with matrix dimensions up to
30000x30000 using real*4 (less than 4GB memory).
I have tried to enlarge the dimension to 50000 or 70000. After approx.
10 hours calculation after calling SSYEVX the only result is a
segmentation fault. I expected the need of about 12 to 20 GB RAM. Are
there any restrictions?
I am using a node of a compute cluster with 256 GB RAM, AMD Opteron
processor and CentOS 64bit Linux system. Below you can see an extract
of my program.
Thank you in advance. I am looking forward to read from you. I really
could need some help.
Kind regards,
Sarah
IMPLICIT NONE
integer*4 dim,lwork,liwork,nfdim
PARAMETER (dim=71000)
PARAMETER (lwork= 80000000)
PARAMETER (liwork=80000000)
PARAMETER (nfdim=71000)
real*4 C(dim,dim),xx(dim,nfdim)
real*4 work(lwork),lambda(dim)
real*4 abstol,vl,vu
integer*4 iwork(liwork),mm,il,iu,ifail(dim),ier
C set up of matrix C ......, nmax <= dim
call SSYEVX('V','I','U',nmax,c,dim,
1 vl,vu,il,iu,abstol,mm,lambda,xx,dim,work,lwork,iwork,ifail,ier)
--
Sarah F. Wulf
CellNetworks-Cluster of Excellence (EXC81), BioQuant,
Heidelberg University
Im Neuenheimer Feld 267
69120 Heidelberg, Germany
Tel. +49-(0)6221-5451349
e-mail sarah.wulf@Domain.Removed
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