partition and input files ?

[xsjtu]

I am confused about the parallel input files,need your help.
I have read the topic http://feap.berkeley.edu/forum/index.php?topic=705.0
1) Does the tangent stiffness matrix formed from the serial run of the parallel feap and write it into the parallel input files,like Ixxx_000x etc. or during the execution of the parallel calculation?
2) If 1) is during the parallel execution ,what is the role of the "MATRix storage equation structure " and "EQUAtion number data" etc. in the followed parallel calculation ? Do them can be omitted ?
3) If one wants construct his own inputs files (for very large FE problems,and the flat file may be stored separately ), could  he form the "MATRix storage" etc. information by himself easily or should use the serial feap functions?
4) Does every parallel executed feap process form its own tangent stiffness matrix using the serial subroutines in directory "program" or the subroutines in directory "parfeap"?
5) The entry function for the serial execution of the parallel feap is in the "feap84.f" or not? And the working flow is serially read into the single flat file Ixxx then get the equations number and other stuffs and then perform the metis decomposition or perform partition firstly then parse the separated "nodes,elements" etc. serially, or  other flow?
 I am so confused! Thanks for any help you may provided!

[FEAP_Admin]

(1) The tangent stiffness is not stored in the files.
(2) The information after the end of the mesh contains all the precomputed message passing information and the precomputed matrix storage needs for each partition.  This must be in the files.
(3) You are welcome to generate your own input files.  Just make sure to follow the format detailed in the parallel manual.
(4) During a parallel run, the files for the serial version of feap are used to compute the element stiffness and residual. These are then assembled into parallel PETSc data structures using the routines in the parfeap folder.
(5) Correct.  If you perform a serial execution of parfeap/feap the entry will be via main/feap84.f.  This reads a serial input file (flat).  GRAPh,node,n will then construct the node graph for the problem and partition it into n pieces using metis.  OUTDomain,yyy,bflg,<bs> will then write the n parallel input files to disk for PETSc matrix type yyy (with blfg=1, the dirichlet nodes will be in the matrix and bs is the optional blocksize hint).