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From: jwhitson@wpi.wpi.edu (John C Whitson KB2GNC)
Newsgroups: comp.sys.encore
Subject: Encore Parallel Threads
Keywords: help, bug
Message-ID: <9691@wpi.wpi.edu>
Date: 15 Mar 90 16:32:22 GMT
Organization: Worcester Polytechnic Institute, Worcester, Mass.
Lines: 64


	I am running the *simplest* threads applications from
	the Encore Parallel Threads Manual (matrix multiply,
	the examples), and the examples have one problem:
	they never complete!! My program sits around and does
	nothing, yet there are also n CPU bound processes
	that are running that it created. I am doing this on
	an 8-processor XPC Encore Multimax, runnning UMAX 4.3
	R4_0.0 with NFS, dated Feb 8 1990.

	Has anyone else experienced this problem? Or perhaps
	knows the fix?? Is there a fix??

	Here is the program:

#include <stdio.h>
#include <thread.h>

int A[9] = { 1,2,3,4,5,6,7,8,9};
int B[9] = { 9,8,7,6,5,4,3,2,1 };
int C[9];

main(argc,argv)	int argc; char *argv[];	{
    extern void startup();
    if (argc != 2) {
	fprintf(stderr,"usage: tst #procs\n");
	exit(1);
       }
    THREADgo(atol(argv[1]),2*1024*1024,startup,0,0,20*1024,0);
    }

void startup()	{
   extern void mult();
   struct { int i; int j; } ij;

   for(ij.i=0;ij.i<3;ij.i++)
       for(ij.j=0;ij.j<3;ij.j++)
	   THREADcreate(mult,&ij,sizeof(ij),ATTACHED,20*1024,0);
   while(THREADjoin());
      printf("%3d %3d %3d %3d %3d %3d %3d %3d %3d\n",
	  C[0], C[1], C[2], C[3], C[4], C[5], C[6], C[7], C[8]);
   }

void mult(ij)	struct { int i; int j; } *ij; {
    register int i;
    register int t=0;
    register int col = 3*ij->i;
    register int row = ij->j;

    for(i=0;i<3;i++) {
       t += A[col]*B[row];
       col++;
       row += 3;
       }
    C[3*ij->i + ij->j] = t;
    }

/******** ENd of Program ********/

-- 
----------  If at first you don't succeed,  so much for skydiving ---------
John Whitson:   Internet: jwhitson@wpi.wpi.edu  Bitnet: jwhitson@wpi.bitnet
73's from KB2GNC/1                         UUCP: uunet!wpi.wpi.edu!jwhitson
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