diff --git a/src/exchangeDonors.C b/src/exchangeDonors.C
index 4e50f66..309b3cd 100644
--- a/src/exchangeDonors.C
+++ b/src/exchangeDonors.C
@@ -35,7 +35,6 @@ void tioga::exchangeDonors(void)
   // and receiving
   //
   pc->getMap(&nsend,&nrecv,&sndMap,&rcvMap);
-  if (nsend == 0) return;
   //
   // create packets to send and receive
   // and initialize them to zero
@@ -74,7 +73,8 @@ void tioga::exchangeDonors(void)
   //
   // communicate donors (comm1)
   //
-  pc->sendRecvPackets(sndPack,rcvPack);
+  pc->sendRecvPackets2(sndPack,rcvPack);
+  if (nsend == 0) return;
   // Initialize linked lists and populate donor data from rcvPack
   for (int ib=0;ib<nblocks;ib++) {
     auto& mb = mblocks[ib];
diff --git a/src/parallelComm.C b/src/parallelComm.C
index b00f246..4f72132 100644
--- a/src/parallelComm.C
+++ b/src/parallelComm.C
@@ -26,15 +26,12 @@
 
 void parallelComm::sendRecvPacketsAll(PACKET *sndPack, PACKET *rcvPack)
 {
-  int i;
-  int *sint,*sreal,*rint,*rreal;
+  int *sint=(int *)malloc(sizeof(int)*numprocs);
+  int *sreal=(int *) malloc(sizeof(int)*numprocs);
+  int *rint=(int *)malloc(sizeof(int)*numprocs);
+  int *rreal=(int *) malloc(sizeof(int)*numprocs);
   //
-  sint=(int *)malloc(sizeof(int)*numprocs);
-  sreal=(int *) malloc(sizeof(int)*numprocs);
-  rint=(int *)malloc(sizeof(int)*numprocs);
-  rreal=(int *) malloc(sizeof(int)*numprocs);
-  //
-  for(i=0;i<numprocs;i++){
+  for(int i=0;i<numprocs;i++){
     sint[i]=sndPack[i].nints;			
     sreal[i]=sndPack[i].nreals;
   }
@@ -42,7 +39,7 @@ void parallelComm::sendRecvPacketsAll(PACKET *sndPack, PACKET *rcvPack)
   MPI_Alltoall(sint,1,MPI_INT,rint,1,MPI_INT,scomm);
   MPI_Alltoall(sreal,1,MPI_INT,rreal,1,MPI_INT,scomm);
   //
-  for(i=0;i<numprocs;i++) {
+  for(int i=0;i<numprocs;i++) {
     rcvPack[i].nints=rint[i];
     rcvPack[i].nreals=rreal[i];
   }
@@ -107,7 +104,7 @@ void parallelComm::sendRecvPacketsAll(PACKET *sndPack, PACKET *rcvPack)
                 &real_request);
 
   MPI_Wait(&int_request, MPI_STATUS_IGNORE);
-  for(i=0;i<numprocs;i++){
+  for(int i=0;i<numprocs;i++){
     if (rcvPack[i].nints > 0) {
       rcvPack[i].intData=(int *) malloc(sizeof(int)*rcvPack[i].nints);
     }
@@ -212,42 +209,166 @@ void parallelComm::sendRecvPacketsAll(PACKET *sndPack, PACKET *rcvPack)
 //   TIOGA_FREE(status);
 // }
 
-void parallelComm::sendRecvPackets(PACKET *sndPack,PACKET *rcvPack)
+void parallelComm::sendRecvPackets2(PACKET *sndPack,PACKET *rcvPack)
 {
-  int i;
-  int *scount,*rcount;
-  int tag,irnum;
-  MPI_Request *request;
-  MPI_Status *status;
+  int *sint=(int *)malloc(sizeof(int)*numprocs);
+  int *sreal=(int *) malloc(sizeof(int)*numprocs);
+  int *rint=(int *)malloc(sizeof(int)*numprocs);
+  int *rreal=(int *) malloc(sizeof(int)*numprocs);
+  // remove when using stl vectors and just init the vectors to 0
+  for(int i=0;i<numprocs;i++){
+    sint[i]=sreal[i]=0;
+    rint[i]=rreal[i]=0;
+  }
+  for(int i=0;i<nsend;i++){
+    sint[sndMap[i]]=sndPack[i].nints;			
+    sreal[sndMap[i]]=sndPack[i].nreals;
+  }
   //
-  scount=(int *)malloc(2*sizeof(int)*nsend);
-  rcount=(int *) malloc(2*sizeof(int)*nrecv);
-  request=(MPI_Request *) malloc(sizeof(MPI_Request)*2*(nsend+nrecv));
-  status=(MPI_Status *) malloc(sizeof(MPI_Status)*2*(nsend+nrecv));
+  MPI_Alltoall(sint,1,MPI_INT,rint,1,MPI_INT,scomm);
+  MPI_Alltoall(sreal,1,MPI_INT,rreal,1,MPI_INT,scomm);
   //
-  for(i=0;i<nsend;i++){
+  for(int i=0;i<nrecv;i++) {
+    rcvPack[i].nints=rint[rcvMap[i]];
+    rcvPack[i].nreals=rreal[rcvMap[i]];
+  }
+
+  int all_snd_nints = std::accumulate(sint, sint + numprocs, 0);
+  int all_rcv_nints = std::accumulate(rint, rint + numprocs, 0);
+  int *all_snd_intData, *all_rcv_intData;
+  all_snd_intData=(int *) malloc(sizeof(int)*all_snd_nints);
+  all_rcv_intData=(int *) malloc(sizeof(int)*all_rcv_nints);
+  for (int i = 0; i < all_snd_nints; i++) {
+    all_snd_intData[i] = 0;
+  }
+  for (int i = 0; i < all_rcv_nints; i++) {
+    all_rcv_intData[i] = 0;
+  }
+  std::vector<int> snd_int_displs(numprocs+1, 0);
+  std::vector<int> rcv_int_displs(numprocs+1, 0);
+  for (int i=1; i <= numprocs; i++) {
+    snd_int_displs[i] = snd_int_displs[i-1] + sint[i-1];
+    rcv_int_displs[i] = rcv_int_displs[i-1] + rint[i-1];
+  }
+  for (int i=0; i < nsend; i++) {
+    int displ = snd_int_displs[sndMap[i]];
+    for(int j=0; j < sint[sndMap[i]]; j++){
+      all_snd_intData[displ+j] = sndPack[i].intData[j];
+    }
+  }
+  MPI_Request int_request;
+  MPI_Ialltoallv(all_snd_intData,
+                sint,
+                snd_int_displs.data(),
+                MPI_INT,
+                all_rcv_intData,
+                rint,
+                rcv_int_displs.data(),
+                MPI_INT,
+                scomm,
+                &int_request);
+
+  int all_snd_nreals = std::accumulate(sreal, sreal + numprocs, 0);
+  int all_rcv_nreals = std::accumulate(rreal, rreal + numprocs, 0);
+  REAL *all_snd_realData, *all_rcv_realData;
+  all_snd_realData=(REAL *) malloc(sizeof(REAL)*all_snd_nreals);
+  all_rcv_realData=(REAL *) malloc(sizeof(REAL)*all_rcv_nreals);
+  for (int i = 0; i < all_snd_nreals; i++) {
+    all_snd_realData[i] = 0;
+  }
+  for (int i = 0; i < all_rcv_nreals; i++) {
+    all_rcv_realData[i] = 0;
+  }
+  std::vector<int> snd_real_displs(numprocs+1, 0);
+  std::vector<int> rcv_real_displs(numprocs+1, 0);
+  for (int i=1; i <= numprocs; i++) {
+    snd_real_displs[i] = snd_real_displs[i-1] + sreal[i-1];
+    rcv_real_displs[i] = rcv_real_displs[i-1] + rreal[i-1];
+  }
+  for (int i=0; i < nsend; i++) {
+    int displ = snd_real_displs[sndMap[i]];
+    for(int j=0; j < sreal[sndMap[i]]; j++){
+      all_snd_realData[displ+j] = sndPack[i].realData[j];
+    }
+  }
+  MPI_Request real_request;
+  MPI_Ialltoallv(all_snd_realData,
+                sreal,
+                snd_real_displs.data(),
+                MPI_DOUBLE,
+                all_rcv_realData,
+                rreal,
+                rcv_real_displs.data(),
+                MPI_DOUBLE,
+                scomm,
+                &real_request);
+
+  // FIXME: here and above I think I should move this a bit lower
+  MPI_Wait(&int_request, MPI_STATUS_IGNORE);
+  for(int i=0;i<nrecv;i++){
+    if (rcvPack[i].nints > 0) {
+      rcvPack[i].intData=(int *) malloc(sizeof(int)*rcvPack[i].nints);
+    }
+    if (rcvPack[i].nreals > 0) {
+      rcvPack[i].realData=(REAL *) malloc(sizeof(REAL)*rcvPack[i].nreals);
+    }
+  }
+
+  // FIXME: here and above I think I should move this a bit lower
+  MPI_Wait(&real_request, MPI_STATUS_IGNORE);
+  for (int i=0; i < nrecv; i++) {
+    int displ = rcv_int_displs[rcvMap[i]];
+    for(int j=0; j < rint[rcvMap[i]]; j++){
+      rcvPack[i].intData[j] = all_rcv_intData[displ+j];
+    }
+  }
+  for (int i=0; i < nrecv; i++) {
+    int displ = rcv_real_displs[rcvMap[i]];
+    for(int j=0; j < rreal[rcvMap[i]]; j++){
+      rcvPack[i].realData[j] = all_rcv_realData[displ+j];
+    }
+  }
+
+  TIOGA_FREE(all_snd_intData);
+  TIOGA_FREE(all_rcv_intData);
+  TIOGA_FREE(all_snd_realData);
+  TIOGA_FREE(all_rcv_realData);
+  TIOGA_FREE(sint);
+  TIOGA_FREE(sreal);
+  TIOGA_FREE(rint);
+  TIOGA_FREE(rreal);
+}
+
+void parallelComm::sendRecvPackets(PACKET *sndPack,PACKET *rcvPack)
+{
+  int *scount=(int *)malloc(2*sizeof(int)*nsend);
+  int *rcount=(int *) malloc(2*sizeof(int)*nrecv);
+  MPI_Request *request=(MPI_Request *) malloc(sizeof(MPI_Request)*2*(nsend+nrecv));
+  MPI_Status *status=(MPI_Status *) malloc(sizeof(MPI_Status)*2*(nsend+nrecv));
+  //
+  for(int i=0;i<nsend;i++){
     scount[2*i]=sndPack[i].nints;			
     scount[2*i+1]=sndPack[i].nreals;
   }
   //
-  irnum=0;
-  tag=1;
+  int irnum=0;
+  int tag=1;
   //
-  for(i=0;i<nrecv;i++)
+  for(int i=0;i<nrecv;i++)
     MPI_Irecv(&(rcount[2*i]),2,MPI_INT,rcvMap[i],tag,scomm,&request[irnum++]);
   //
-  for(i=0;i<nsend;i++)
+  for(int i=0;i<nsend;i++)
     MPI_Isend(&(scount[2*i]),2,MPI_INT,sndMap[i],tag,scomm,&request[irnum++]);
   //
   MPI_Waitall(irnum,request,status);
-  for(i=0;i<nrecv;i++)
+  for(int i=0;i<nrecv;i++)
     {
       rcvPack[i].nints=rcount[2*i];
       rcvPack[i].nreals=rcount[2*i+1];
     }
   //
   irnum=0;
-  for(i=0;i<nrecv;i++)
+  for(int i=0;i<nrecv;i++)
     {
       if (rcvPack[i].nints > 0) {
 	tag=1;
@@ -265,7 +386,7 @@ void parallelComm::sendRecvPackets(PACKET *sndPack,PACKET *rcvPack)
       }
     }
   //
-  for(i=0;i<nsend;i++)
+  for(int i=0;i<nsend;i++)
     {
       if (sndPack[i].nints > 0){
 	tag=1;
@@ -290,34 +411,28 @@ void parallelComm::sendRecvPackets(PACKET *sndPack,PACKET *rcvPack)
 
 void parallelComm::sendRecvPacketsCheck(PACKET *sndPack,PACKET *rcvPack)
 {
-  int i;
-  int *scount,*rcount;
-  int tag,irnum;
-  MPI_Request *request;
-  MPI_Status *status;
+  int *scount=(int *)malloc(2*sizeof(int)*nsend);
+  int *rcount=(int *) malloc(2*sizeof(int)*nrecv);
+  MPI_Request *request=(MPI_Request *) malloc(sizeof(MPI_Request)*2*(nsend+nrecv));
+  MPI_Status *status=(MPI_Status *) malloc(sizeof(MPI_Status)*2*(nsend+nrecv));
   //
-  scount=(int *)malloc(2*sizeof(int)*nsend);
-  rcount=(int *) malloc(2*sizeof(int)*nrecv);
-  request=(MPI_Request *) malloc(sizeof(MPI_Request)*2*(nsend+nrecv));
-  status=(MPI_Status *) malloc(sizeof(MPI_Status)*2*(nsend+nrecv));
-  //
-  for(i=0;i<nsend;i++){
+  for(int i=0;i<nsend;i++){
     scount[2*i]=sndPack[i].nints;			
     scount[2*i+1]=sndPack[i].nreals;
   }
   //
-  irnum=0;
-  tag=1;
+  int irnum=0;
+  int tag=1;
   //
-  for(i=0;i<nrecv;i++)
+  for(int i=0;i<nrecv;i++)
     MPI_Irecv(&(rcount[2*i]),2,MPI_INT,rcvMap[i],tag,scomm,&request[irnum++]);
   //
-  for(i=0;i<nsend;i++)
+  for(int i=0;i<nsend;i++)
     MPI_Isend(&(scount[2*i]),2,MPI_INT,sndMap[i],tag,scomm,&request[irnum++]);
   //
   MPI_Waitall(irnum,request,status);
 
-  for(i=0;i<nrecv;i++)
+  for(int i=0;i<nrecv;i++)
     {
       rcvPack[i].nints=rcount[2*i];
       rcvPack[i].nreals=rcount[2*i+1];
@@ -333,7 +448,7 @@ void parallelComm::sendRecvPacketsCheck(PACKET *sndPack,PACKET *rcvPack)
   //  }
   //
   irnum=0;
-  for(i=0;i<nrecv;i++)
+  for(int i=0;i<nrecv;i++)
     {
       if (rcvPack[i].nints > 0) {
 	tag=1;
@@ -351,7 +466,7 @@ void parallelComm::sendRecvPacketsCheck(PACKET *sndPack,PACKET *rcvPack)
       }
     }
   //
-  for(i=0;i<nsend;i++)
+  for(int i=0;i<nsend;i++)
     {
       if (sndPack[i].nints > 0){
 	tag=1;
@@ -376,8 +491,6 @@ void parallelComm::sendRecvPacketsCheck(PACKET *sndPack,PACKET *rcvPack)
 
 void parallelComm::setMap(int ns,int nr, int *snd,int *rcv)
 {
-  int i;
-  //
   if (sndMap) TIOGA_FREE(sndMap); sndMap=NULL;
   if (rcvMap) TIOGA_FREE(rcvMap); rcvMap=NULL;
   //
@@ -386,8 +499,8 @@ void parallelComm::setMap(int ns,int nr, int *snd,int *rcv)
   sndMap=(int *) malloc(sizeof(int)*nsend);
   rcvMap=(int *) malloc(sizeof(int)*nrecv);
   //
-  for(i=0;i<nsend;i++) sndMap[i]=snd[i];
-  for(i=0;i<nrecv;i++) rcvMap[i]=rcv[i];
+  for(int i=0;i<nsend;i++) sndMap[i]=snd[i];
+  for(int i=0;i<nrecv;i++) rcvMap[i]=rcv[i];
 }
 
 void parallelComm::getMap(int *ns, int *nr, int **snd,int **rcv)
@@ -402,17 +515,16 @@ void parallelComm::getMap(int *ns, int *nr, int **snd,int **rcv)
   
 void parallelComm::clearPackets(PACKET *sndPack, PACKET *rcvPack)
 {
-  int i;
   //
   // free Send and recv data
   //
-  for(i=0;i<nsend;i++)
+  for(int i=0;i<nsend;i++)
     {
       if (sndPack[i].intData) TIOGA_FREE(sndPack[i].intData);
       if (sndPack[i].realData) TIOGA_FREE(sndPack[i].realData);
       sndPack[i].nints=sndPack[i].nreals=0;
     }
-  for(i=0;i<nrecv;i++)
+  for(int i=0;i<nrecv;i++)
     {
       if (rcvPack[i].intData) TIOGA_FREE(rcvPack[i].intData);
       if (rcvPack[i].realData) TIOGA_FREE(rcvPack[i].realData);
@@ -424,20 +536,16 @@ void parallelComm::clearPackets(PACKET *sndPack, PACKET *rcvPack)
 
 void parallelComm::initPackets(PACKET *sndPack, PACKET *rcvPack)
 {
-  int i;
-  //
-  for(i=0;i<nsend;i++)     
+  for(int i=0;i<nsend;i++)     
     {
       sndPack[i].nints=sndPack[i].nreals=0;
       sndPack[i].intData=NULL;
       sndPack[i].realData=NULL;
     }
-  //
-  for(i=0;i<nrecv;i++)     
+  for(int i=0;i<nrecv;i++)     
     {
       rcvPack[i].nints=rcvPack[i].nreals=0;
       rcvPack[i].intData=NULL;
       rcvPack[i].realData=NULL;
     }
-  //
 }
diff --git a/src/parallelComm.h b/src/parallelComm.h
index c941a1e..6796e7a 100644
--- a/src/parallelComm.h
+++ b/src/parallelComm.h
@@ -58,6 +58,8 @@ class parallelComm {
 
   void sendRecvPacketsAll(PACKET *sndPack, PACKET *rcvPack);
 
+  void sendRecvPackets2(PACKET *sndPack, PACKET *rcvPack);
+
   void sendRecvPackets(PACKET *sndPack, PACKET *rcvPack);
 
   void sendRecvPacketsCheck(PACKET *sndPack, PACKET *rcvPack);
diff --git a/src/tioga.C b/src/tioga.C
index 3405419..503249b 100644
--- a/src/tioga.C
+++ b/src/tioga.C
@@ -492,7 +492,9 @@ void tioga::performConnectivity(void)
   this->myTimer("tioga::exchangeDonors",1);
   //this->reduce_fringes();
   //outputStatistics();
-  MPI_Allreduce(&ihigh,&ihighGlobal,1,MPI_INT,MPI_MAX,scomm);
+  //MPI_Allreduce(&ihigh,&ihighGlobal,1,MPI_INT,MPI_MAX,scomm);
+  assert(ihigh == 0);
+  ihighGlobal = 0;
   //if (ihighGlobal) {
   this->myTimer("tioga::getCellIblanks",0);
   for (int ib=0;ib<nblocks;ib++) {