diff --git a/util/psb_mat_dist_mod.f90 b/util/psb_mat_dist_mod.f90
index ce47c421..07f3804d 100644
--- a/util/psb_mat_dist_mod.f90
+++ b/util/psb_mat_dist_mod.f90
@@ -37,7 +37,7 @@ module psb_mat_dist_mod
 contains
 
   subroutine dmatdistf (a_glob, a, parts, ictxt, desc_a,&
-       & b_glob, b, info, inroot,fmt)
+       & b_glob, b, info, inroot,fmt,nb)
     !
     ! an utility subroutine to distribute a matrix among processors
     ! according to a user defined data distribution, using 
@@ -105,7 +105,7 @@ contains
     real(kind(1.d0)), allocatable  :: b(:)
     type (psb_desc_type)       :: desc_a
     integer, intent(out)       :: info
-    integer, optional          :: inroot
+    integer, optional          :: inroot,nb
     character(len=5), optional :: fmt
     interface 
 
@@ -122,12 +122,12 @@ contains
     integer                     :: np, iam 
     integer                     :: ircode, length_row, i_count, j_count,&
          & k_count, blockdim, root, liwork, nrow, ncol, nnzero, nrhs,&
-         & i,j,k, ll, nz, isize, iproc, nnr, err, err_act, int_err(5)
+         & i,j,k, ll, nz, isize, iproc, nnr, err, err_act, int_err(5),nb_
     integer, allocatable            :: iwork(:)
     character                   :: afmt*5, atyp*5
     integer, allocatable          :: irow(:),icol(:)
     real(kind(1.d0)), allocatable :: val(:)
-    integer, parameter          :: nb=30
+    integer, parameter          :: nbdef=30
     real(kind(1.d0))            :: t0, t1, t2, t3, t4, t5
     character(len=20)           :: name, ch_err
 
@@ -142,6 +142,11 @@ contains
     else
       root = 0
     end if
+    if (present(nb)) then
+      nb_ = max(nb,1)
+    else
+      nb_ = nbdef
+    end if
     call psb_info(ictxt, iam, np)     
 
     if (iam == root) then
@@ -203,10 +208,11 @@ contains
       call psb_errpush(info,name,a_err=ch_err)
       goto 9999
     end if
-    isize = max(3*nb,ncol)
 
 
-    allocate(val(nb*ncol),irow(nb*ncol),icol(nb*ncol),stat=info)
+    isize = ((nnzero+nrow)/nrow) * nb_
+    isize = max(isize,4*nb_) 
+    allocate(val(isize),irow(isize),icol(isize),stat=info)
     if(info/=0) then
       info=4010
       ch_err='Allocate'
@@ -225,7 +231,7 @@ contains
         iproc   = iwork(1) 
         do 
           j_count = j_count + 1 
-          if (j_count-i_count >= nb) exit
+          if (j_count-i_count >= nb_) exit
           if (j_count > nrow) exit
           call parts(j_count,nrow,np,iwork, length_row)
           if (length_row /= 1 ) exit
@@ -240,9 +246,9 @@ contains
           ll = 0
           do i= i_count, j_count-1
             call psb_sp_getrow(i,a_glob,nz,&
-                 & irow(ll+1:),icol(ll+1:),val(ll+1:), info)
+                 & irow,icol,val,info,nzin=ll,append=.true.)
             if (info /= 0) then            
-              if (nz >min(size(irow(ll+1:)),size(icol(ll+1:)),size(val(ll+1:)))) then 
+              if (nz > min(size(irow(ll+1:)),size(icol(ll+1:)),size(val(ll+1:)))) then 
                 write(0,*) 'Allocation failure? This should not happen!'
               end if
               call psb_errpush(info,name,a_err=ch_err)
@@ -271,8 +277,11 @@ contains
             call psb_snd(ictxt,nnr,iproc)
             call psb_snd(ictxt,ll,iproc)
             call psb_snd(ictxt,irow(1:ll),iproc)
+            call psb_rcv(ictxt,ll,iproc)
             call psb_snd(ictxt,icol(1:ll),iproc)
+            call psb_rcv(ictxt,ll,iproc)
             call psb_snd(ictxt,val(1:ll),iproc)
+            call psb_rcv(ictxt,ll,iproc)
             call psb_snd(ictxt,b_glob(i_count:j_count-1),iproc)
             call psb_rcv(ictxt,ll,iproc)
           endif
@@ -294,10 +303,15 @@ contains
 
             endif
             call psb_rcv(ictxt,irow(1:ll),root)
+            call psb_snd(ictxt,ll,root)
+
             call psb_rcv(ictxt,icol(1:ll),root)
+            call psb_snd(ictxt,ll,root)
+            
             call psb_rcv(ictxt,val(1:ll),root)
-            call psb_rcv(ictxt,b_glob(i_count:i_count+nnr-1),root)
             call psb_snd(ictxt,ll,root)
+
+            call psb_rcv(ictxt,b_glob(i_count:i_count+nnr-1),root)
             call psb_spins(ll,irow,icol,val,a,desc_a,info)
             if(info/=0) then
               info=4010
@@ -313,6 +327,8 @@ contains
               call psb_errpush(info,name,a_err=ch_err)
               goto 9999
             end if
+            call psb_snd(ictxt,ll,root)
+            
           endif
         endif
 
@@ -328,7 +344,7 @@ contains
             ll = 0
             do i= i_count, i_count
               call psb_sp_getrow(i,a_glob,nz,&
-                   & irow(ll+1:),icol(ll+1:),val(ll+1:), info)
+                 & irow,icol,val,info,nzin=ll,append=.true.)
               if (info /= 0) then            
                 if (nz >min(size(irow(ll+1:)),size(icol(ll+1:)),size(val(ll+1:)))) then 
                   write(0,*) 'Allocation failure? This should not happen!'
@@ -359,8 +375,11 @@ contains
             else
               call psb_snd(ictxt,ll,k_count)
               call psb_snd(ictxt,irow(1:ll),k_count)
+              call psb_rcv(ictxt,ll,k_count)
               call psb_snd(ictxt,icol(1:ll),k_count)
+              call psb_rcv(ictxt,ll,k_count)
               call psb_snd(ictxt,val(1:ll),k_count)
+              call psb_rcv(ictxt,ll,k_count)
               call psb_snd(ictxt,b_glob(i_count),k_count)
               call psb_rcv(ictxt,ll,k_count)
             endif
@@ -369,10 +388,12 @@ contains
 
               call psb_rcv(ictxt,ll,root)
               call psb_rcv(ictxt,irow(1:ll),root)
+              call psb_snd(ictxt,ll,root)
               call psb_rcv(ictxt,icol(1:ll),root)
+              call psb_snd(ictxt,ll,root)
               call psb_rcv(ictxt,val(1:ll),root)
-              call psb_rcv(ictxt,b_glob(i_count),root)
               call psb_snd(ictxt,ll,root)
+              call psb_rcv(ictxt,b_glob(i_count),root)
               call psb_spins(ll,irow,icol,val,a,desc_a,info)
               if(info/=0) then
                 info=4010
@@ -388,6 +409,7 @@ contains
                 call psb_errpush(info,name,a_err=ch_err)
                 goto 9999
               end if
+              call psb_snd(ictxt,ll,root)
             endif
           endif
         end do
@@ -463,7 +485,7 @@ contains
 
 
   subroutine dmatdistv (a_glob, a, v, ictxt, desc_a,&
-       & b_glob, b, info, inroot,fmt)
+       & b_glob, b, info, inroot,fmt,nb)
     !
     ! an utility subroutine to distribute a matrix among processors
     ! according to a user defined data distribution, using 
@@ -529,18 +551,18 @@ contains
     real(kind(1.d0)), allocatable  :: b(:)
     type (psb_desc_type)       :: desc_a
     integer, intent(out)       :: info
-    integer, optional          :: inroot
+    integer, optional          :: inroot,nb
     character(len=5), optional :: fmt
 
     integer                     :: np, iam
     integer                     :: ircode, length_row, i_count, j_count,&
          & k_count, blockdim, root, liwork, nrow, ncol, nnzero, nrhs,&
-         & i,j,k, ll, nz, isize, iproc, nnr, err, err_act, int_err(5)
+         & i,j,k, ll, nz, isize, iproc, nnr, err, err_act, int_err(5),nb_
     integer, allocatable            :: iwork(:)
     character                   :: afmt*5, atyp*5
     integer, allocatable          :: irow(:),icol(:)
     real(kind(1.d0)), allocatable :: val(:)
-    integer, parameter          :: nb=30
+    integer, parameter          :: nbdef=30
     real(kind(1.d0))            :: t0, t1, t2, t3, t4, t5
     character(len=20)  :: name, ch_err
 
@@ -555,6 +577,11 @@ contains
     else
       root = 0
     end if
+    if (present(nb)) then
+      nb_ = max(nb,1)    
+    else
+      nb_ = nbdef
+    end if
 
     call psb_info(ictxt, iam, np)     
     if (iam == root) then
@@ -577,6 +604,7 @@ contains
 
       nnzero = size(a_glob%aspk)
       nrhs   = 1
+      
     end if
     ! broadcast informations to other processors
     call psb_bcast(ictxt,nrow, root)
@@ -593,6 +621,29 @@ contains
       goto 9999
     endif
 
+    if (iam /= root) then 
+      allocate(a_glob%ia1(nnzero),&
+           & a_glob%ia2(nrow+1),a_glob%aspk(nnzero),a_glob%pl(1),a_glob%pr(1),stat=info)
+      
+      if(info/=0) then
+        info=4010
+        ch_err='psb_cdall'
+        call psb_errpush(info,name,a_err=ch_err)
+        goto 9999
+      end if
+      a_glob%pl=0
+      a_glob%pr=0
+    end if
+    call psb_bcast(ictxt,a_glob%m,root)
+    call psb_bcast(ictxt,a_glob%k,root)
+    call psb_bcast(ictxt,a_glob%fida,root)
+    call psb_bcast(ictxt,a_glob%descra,root)
+    call psb_bcast(ictxt,a_glob%infoa(1:psb_ifasize_),root)
+    call psb_bcast(ictxt,a_glob%ia1(1:nnzero),root)
+    call psb_bcast(ictxt,a_glob%aspk(1:nnzero),root)
+    call psb_bcast(ictxt,a_glob%ia2(1:nrow+1),root)
+    
+    
     call psb_cdall(ictxt,desc_a,info,vg=v)
     if(info/=0) then
       info=4010
@@ -615,10 +666,11 @@ contains
       call psb_errpush(info,name,a_err=ch_err)
       goto 9999
     end if
-    isize = max(3*nb,ncol)
 
 
-    allocate(val(nb*ncol),irow(nb*ncol),icol(nb*ncol),stat=info)
+    isize = ((nnzero+nrow)/nrow) * nb_
+    isize = max(isize,4*nb_) 
+    allocate(val(isize),irow(isize),icol(isize),stat=info)
     if(info/=0) then
       info=4010
       ch_err='Allocate'
@@ -635,7 +687,7 @@ contains
 
       do 
         j_count = j_count + 1 
-        if (j_count-i_count >= nb) exit
+        if (j_count-i_count >= nb_) exit
         if (j_count > nrow) exit
         if (v(j_count) /= iproc ) exit
       end do
@@ -643,12 +695,13 @@ contains
       ! now we should insert rows i_count..j_count-1
       nnr = j_count - i_count
 
-      if (iam == root) then
+
+      if (iproc == iam) then
         
         ll = 0
         do i= i_count, j_count-1
           call psb_sp_getrow(i,a_glob,nz,&
-               & irow(ll+1:),icol(ll+1:),val(ll+1:), info)
+               & irow,icol,val,info,nzin=ll,append=.true.)
           if (info /= 0) then            
             if (nz >min(size(irow(ll+1:)),size(icol(ll+1:)),size(val(ll+1:)))) then 
               write(0,*) 'Allocation failure? This should not happen!'
@@ -658,71 +711,23 @@ contains
           end if
           ll = ll + nz
         end do
-
-        if (iproc == iam) then
-          call psb_spins(ll,irow,icol,val,a,desc_a,info)
-          if(info/=0) then
-            info=4010
-            ch_err='psb_spins'
-            call psb_errpush(info,name,a_err=ch_err)
-            goto 9999
-          end if
-
-          call psb_geins(nnr,(/(i,i=i_count,j_count-1)/),b_glob(i_count:j_count-1),&
-               & b,desc_a,info)
-          if(info/=0) then
-            info=4010
-            ch_err='dsins'
-            call psb_errpush(info,name,a_err=ch_err)
-            goto 9999
-          end if
-        else
-          call psb_snd(ictxt,nnr,iproc)
-          call psb_snd(ictxt,ll,iproc)
-          call psb_snd(ictxt,irow(1:ll),iproc)
-          call psb_snd(ictxt,icol(1:ll),iproc)
-          call psb_snd(ictxt,val(1:ll),iproc)
-          call psb_snd(ictxt,b_glob(i_count:j_count-1),iproc)
-          call psb_rcv(ictxt,ll,iproc)
-        endif
-      else if (iam /= root) then
-
-        if (iproc == iam) then
-          call psb_rcv(ictxt,nnr,root)
-          call psb_rcv(ictxt,ll,root)
-          if (ll > size(val)) then 
-            write(0,*) iam,'need to reallocate ',ll
-            deallocate(val,irow,icol)
-            allocate(val(ll),irow(ll),icol(ll),stat=info)
-            if(info/=0) then
-              info=4010
-              ch_err='Allocate'
-              call psb_errpush(info,name,a_err=ch_err)
-              goto 9999
-            end if
-          endif
-          call psb_rcv(ictxt,irow(1:ll),root)
-          call psb_rcv(ictxt,icol(1:ll),root)
-          call psb_rcv(ictxt,val(1:ll),root)
-          call psb_rcv(ictxt,b_glob(i_count:i_count+nnr-1),root)
-          call psb_snd(ictxt,ll,root)
-
-          call psb_spins(ll,irow,icol,val,a,desc_a,info)
-          if(info/=0) then
-            info=4010
-            ch_err='spins'
-            call psb_errpush(info,name,a_err=ch_err)
-            goto 9999
-          end if
-          call psb_geins(nnr,(/(i,i=i_count,i_count+nnr-1)/),&
-               & b_glob(i_count:i_count+nnr-1),b,desc_a,info)
-          if(info/=0) then
-            info=4010
-            ch_err='psdsins'
-            call psb_errpush(info,name,a_err=ch_err)
-            goto 9999
-          end if
-        endif
+        
+        call psb_spins(ll,irow,icol,val,a,desc_a,info)
+        if(info/=0) then
+          info=4010
+          ch_err='psb_spins'
+          call psb_errpush(info,name,a_err=ch_err)
+          goto 9999
+        end if
+        
+        call psb_geins(nnr,(/(i,i=i_count,j_count-1)/),b_glob(i_count:j_count-1),&
+             & b,desc_a,info)
+        if(info/=0) then
+          info=4010
+          ch_err='dsins'
+          call psb_errpush(info,name,a_err=ch_err)
+          goto 9999
+        end if
       endif
       i_count = j_count
 
@@ -989,7 +994,7 @@ contains
           ll = 0
           do i= i_count, j_count-1
             call psb_sp_getrow(i,a_glob,nz,&
-                 & irow(ll+1:),icol(ll+1:),val(ll+1:), info)
+                 & irow,icol,val,info,nzin=ll,append=.true.)
             if (info /= 0) then            
               if (nz >min(size(irow(ll+1:)),size(icol(ll+1:)),size(val(ll+1:)))) then 
                 write(0,*) 'Allocation failure? This should not happen!'
@@ -1077,7 +1082,7 @@ contains
             ll = 0
             do i= i_count, i_count
               call psb_sp_getrow(i,a_glob,nz,&
-                   & irow(ll+1:),icol(ll+1:),val(ll+1:), info)
+                   & irow,icol,val,info,nzin=ll,append=.true.)
               if (info /= 0) then            
                 if (nz >min(size(irow(ll+1:)),size(icol(ll+1:)),size(val(ll+1:)))) then 
                   write(0,*) 'Allocation failure? This should not happen!'
@@ -1395,7 +1400,7 @@ contains
         ll = 0
         do i= i_count, j_count-1
           call psb_sp_getrow(i,a_glob,nz,&
-               & irow(ll+1:),icol(ll+1:),val(ll+1:), info)
+               & irow,icol,val,info,nzin=ll,append=.true.)
           if (info /= 0) then            
             if (nz >min(size(irow(ll+1:)),size(icol(ll+1:)),size(val(ll+1:)))) then 
               write(0,*) 'Allocation failure? This should not happen!'