The SIF decoder sizes are gathered in the file $MYSIFDEC/precision/config/sifdec.siz, which contains the following parameters.
| Parameter | Brief description |
| NMAX | the maximum number of variables in a problem |
| NGMAX | the maximum number of groups in a problem |
| NGRMAX | the maximum number of different group types |
| NGPVMX | the maximum number of real parameters associated with groups |
| NELMAX | the maximum number of nonlinear element functions in a problem |
| NLMAX | the maximum number of different nonlinear element types |
| NEVMAX | the maximum total number of elemental variables in a problem |
| NINMAX | the maximum total number of internal variables in a problem |
| NSETVC | the maximum number of nonzero entries in an element Hessian |
| NEPVMX | the maximum number of real parameters associated with nonlinear elements |
| LA | the maximum number of nonzero entries in the linear elements |
| NINDEX | the maximum number of integer parameters in a problem |
| NRLNDX | the maximum number of real parameters in a problem |
| NBMAX | the maximum number of different sets of bounds on the variables |
| which may be specified | |
| NSMAX | the maximum number of different sets of starting points which may |
| be specified | |
| NOBMAX | the maximum number of different sets of bounds on the objective |
| function which may be specified |
Definitions of the terms used here are given in [2]. These parameters are assigned a value upon initial installation of SifDec on the system. These values should be changed according to the SIF-decoder messages issued at decode-time, and SifDec should be rebuilt.