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#include <stdio.h>
#include "MPIutils.hh"
#include "MPIO.hh"
void MPIO::sendSlice(int z,float *data,MPI_Request *req){
int iz = z - localorigin[2];
if(iz<0 || iz>=localdims[2]) return;
//printf("PE(%u) send slice z=%u. iz=%u\n",myid,z,iz);
// z == the tag
//printf("localdims[0]*localdims[1]=%u iz=%u\n",localdims[0]*localdims[1],iz);
// if(isRoot())
//comm.iSend(root,z,localdims[0]*localdims[1],
// data+localdims[0]*localdims[1]*iz,req[iz]);
//else
comm.isSend(root,z,localdims[0]*localdims[1],
data+localdims[0]*localdims[1]*iz,req[iz]);
//for(int i=0;i<4;i++) //printf("\tslicedata[%u]@z(%u) = %f\n",i,iz,(data+localdims[0]*localdims[1]*iz)[i]);
//printf("PE(%u) send %u complete\n",myid,iz);
}
void MPIO::requestSlice(int z,float *slicebuffer,MPI_Request *req){
// skip to z
//loop (foreach p of pe's)
if(!isRoot()) return;
//printf("PE(%u) request slice %u\n",myid,z);
for(int offset=0,p=0,reqindex=0;p<comm.numProcs();p++) {
// if within z-range, compute nelem based on dims at p
int dindex = 3*p;
int *idims = gdims + dindex;
int *iorigin = gorigins + dindex;
int iz = z-iorigin[2];
if(iz<0 || iz>=idims[2]) continue;
comm.iRecv(p,z,idims[0]*idims[1],slicebuffer+offset,req[reqindex++]);
//printf("reqslice(%u):MPI_Request=%u\n",iz,req[reqindex-1]);
offset+=idims[0]*idims[1];
}
// break if outside of z-range (dangerous if non-canonical proc layout)
}
void MPIO::waitForSlice(int z,float *slicebuffer,float *destbuffer,MPI_Request *req){
if(!isRoot()) return;
// could do this 8k at a time
// loop for each p of pe's
// if within z-range, compute nelem based on dims at p
// wait for current request.
// re-copy based on offset & origin
sliceallwait.start();
for(int p=0,reqindex=0;p<comm.numProcs();p++) {
// if within z-rang e, compute nelem based on dims at p
int dindex = 3*p;
int *idims = gdims + dindex;
int *iorigin = gorigins + dindex;
int iz = z-iorigin[2];
if(iz<0 || iz>=idims[2]) continue;
MPI_Status stat;
//printf("waitfor(%u):MPI_Request=%u\n",iz,req[reqindex]);
slicewait.start();
comm.wait(req[reqindex++],stat); // frees request object too
slicewait.stop();
// get information out of the status object!!!!
slicecollect.start();
int offset = iorigin[1]*globaldims[0] + iorigin[0];
for(int idx=0,pos=offset,j=0;j<idims[1];j++,pos+=(globaldims[0]-idims[0]))
for(int i=0;i<idims[0];i++)
destbuffer[pos++]=slicebuffer[idx++];
slicecollect.stop();
}
sliceallwait.stop();
// proclist array
}
MPIO::MPIO(IObase *io,MPIcomm &c):file(io),comm(c){
for(int i=0;i<3;i++) globaldims[i]=localdims[i]=localorigin[i]=0;
int *rootarray;
myid = comm.rank();
//printf("my rank = %u\n",myid);
if(!myid) rootarray = new int[comm.numProcs()];
int rootscale = file?1:0;
//printf("rootscale[pid=%u] = %u\n",myid,rootscale);
comm.gather(0,1,&rootscale,rootarray); // gather to 0
globaldims[0]=globaldims[1]=globaldims[2]=0;
if(!myid){
for(int count=0,p=0;p<comm.numProcs();p++){
//printf("rootarray[%u]=%u\n",p,rootarray[p]);
if(rootarray[p]) count++;
}
if(count<=0 || count>1){
fprintf(stderr,"MPIO only accepts a single IO node right now.\n");
fprintf(stderr,"You chose %u io nodes\n",count);
fprintf(stderr,"I will select only the first one\n");
}
for(root=-1,p=0;p<comm.numProcs() && root<0;p++)
if(rootarray[p]) root=p;
delete rootarray;
}
comm.bcast(0,root); // now everyone knows root
//printf("broadcasting root node = %u\n",root);
}
MPIO::~MPIO(){
char buffer[32];
sprintf(buffer,"PE(%3u)",comm.rank());
if(myid==root) {
sprintf(buffer+7,"slicewait"); slicewait.print(buffer);
sprintf(buffer+7,"slicewrite"); slicewrite.print(buffer);
sprintf(buffer+7,"slicecollect"); slicecollect.print(buffer);
//sprintf(buffer+7,"sliceselect"); sliceselect.print(buffer);
sprintf(buffer+7,"sliceallwait"); sliceallwait.print(buffer);
}
}
void MPIO::setLocalDims(int rank,int *origin, int *dims){
if(rank!=3) perror("MPIO is only for 3D IO for now (sorry)!");
if(isRoot()){
gorigins = new int[3*comm.numProcs()];
gdims = new int[3*comm.numProcs()];
}
else gdims=gorigins=0; // null for everyone else
for(int i=0;i<3;i++) {
//printf("localdims-n-origin[%u] = %u:%u\n",i,dims[i],origin[i]);
localdims[i]=dims[i];
localorigin[i]=origin[i];
}
comm.gather(root,3,localdims,gdims);
comm.gather(root,3,localorigin,gorigins);
//if(isRoot()) for(i=0;i<3*comm.numProcs();i++)
//printf("gdims-n-origin[%u] = %u:%u\n",i,gdims[i],gorigins[i]);
globaldims[0]=globaldims[1]=globaldims[2]=0;
if(isRoot())
for(int p=0,last=3*comm.numProcs();p<last;p++){
//printf("globaldims[%u]: gdims[%u]+gorigins[%u] = %u\n",
// p%3,p,p,gdims[p],gorigins[p]);
if(globaldims[p%3] < gdims[p]+gorigins[p])
globaldims[p%3] = gdims[p]+gorigins[p];
}
// rebroadcast globaldims to all PE's
comm.bcast(root,3,globaldims);
}
int MPIO::write(IObase::DataType type,int rank,int *dims,void *data){
int recalc_layout=0;
if(rank!=3) recalc_layout=1;
for(int i=0;i<rank;i++) if(localdims[i]!=dims[i]) recalc_layout=1;
if(recalc_layout) setLocalDims(rank,localorigin,dims);
switch(type){
case IObase::Float32:
write((float*)data);
break;
case IObase::Float64:
default:
break;
}
return 1; // for now, no error checking
}
void MPIO::write(float *data){
MPI_Request *sendreq = new MPI_Request[localdims[2]];
typedef float *floatP;
int sliceindex=0;
floatP slicebuffer[3]; // double-buffer the slices as they arrive
typedef MPI_Request *MPI_RequestP;
MPI_RequestP recvreq[2];
// the third one is a scratch buffer for reorganizing the slice
if(isRoot()){
for(int i=0;i<3;i++) slicebuffer[i] = new float[globaldims[0]*globaldims[1]];
for(i=0;i<2;i++) recvreq[i] = new MPI_Request[comm.numProcs()];
}
if(isRoot()){
// puts("request initial slice");
requestSlice(0,slicebuffer[0],recvreq[0]);
}
// not good! Everyone is sending a slice here!
sendSlice(0,data,sendreq);
// hide latency behind the costly io->reserveChunk operation
if(isRoot()) file->reserveStream(IObase::Float32,3,globaldims);
int writecount=0;
for(int i=1;i<globaldims[2];i++){
// comm.barrier();
if(isRoot())
requestSlice(i,slicebuffer[i%2],recvreq[i%2]);
sendSlice(i,data,sendreq); // jms
if(isRoot()) {
waitForSlice(i-1,slicebuffer[(i-1)%2],slicebuffer[2],recvreq[(i-1)%2]);
writecount+=globaldims[0]*globaldims[1];
slicewrite.start();
file->writeStream(slicebuffer[2],globaldims[0]*globaldims[1]);
slicewrite.stop();
}
}
if(isRoot()){
waitForSlice(i-1,slicebuffer[(i-1)%2],slicebuffer[2],recvreq[(i-1)%2]);
file->writeStream(slicebuffer[2],globaldims[0]*globaldims[1]);
writecount+=globaldims[0]*globaldims[1];
// do requestfree (double-buffered request free-s)
for(i=0;i<3;i++) delete slicebuffer[i]; // free everything up
for(i=0;i<2;i++) delete recvreq[i];
}
MPI_Status stat;
for(i=0;i<localdims[2];i++) comm.wait(sendreq[i],stat);
delete sendreq;
}
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