memory problem

Which parameter should be changed?

*** ERROR # 381 ***
  Allocated working storage insufficient.
  Available memory = 2157 MB.
  Required memory = 3548 MB.
  Number of vectors in modal space = 5628.
  Number of eigenvectors = 6.
  Specifying number of modes in EIGRL card of modal subcase may solve
  this issue. Or, set param NUMEG to a value higher than the number of
  vectors in modal space.
  ...