Hans, That looks like over 80 megabytes just for the dynamically allocated "node" instances:
85000 * 30 * (8 + 8) * 2 If I understand correctly, all Cygwin app memory comes out of a single pool (hence the Cygwin heap size registry entry), so a proper accounting of available memory must take the other concurrently executing Cygwin applications into account. Randall Schulz Mountain View, CA USA At 18:00 2002-09-24, Hans Horn wrote: >Igor, > >"Igor Pechtchanski" <[EMAIL PROTECTED]> wrote in message >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > Don't forget the object headers - depending on which options you use, they > > can be 8 bytes per object. It would really help to see the source of the > > crashing program, at least the snippet with the allocation and > dereferencing. > >Are there options that cost less (in terms of object headers) that the >defaults? > >Allrighty, here's the essence of what's going on: > >// compiled with : gcc -O2 tst.cpp -o tst -lstdc++ >// gcc version: 3.2 > >#define NUM_POINTS 85000 >#define NON_ZERO 30 > >// problem: have a collection of NUM_POINTS points, >// - each point has attached ca 2800 byte descriptive info >// - each point has two kinds (left and right) of neighbors. >// actual neighborhood of all points is given by a very sparse >// NUM_POINTS * NUM_POINTS matrix, >// having on average only NON_ZERO non-zero elements per row/column. > >#include <stdio.h> >#include <iostream.h> >#include <assert.h> > >// an element of a linked list >typedef struct node { > node (int _v, node* _n) : v(_v), next(_n) {} > int v; > node* next; >}; > >int main (int argc, char** argv) { > // allocate descriptions of points > char** points = new char*[NUM_POINTS]; assert(points); > for (int i = 0; i < NUM_POINTS; i++) { > points[i] = new char[2800]; assert(points[i]); > } > cout << "inited points[]" << endl; > > // represent neighborhood for each point via linked lists : > node** adjl = new node*[NUM_POINTS]; assert(adjl); // neighbors to the left > node** adjr = new node*[NUM_POINTS]; assert(adjr); // neighbors to the > right > for (int i = 0; i < NUM_POINTS; i++) { adjl[i] = adjr[i] = NULL; } > for (int i = 0; i < NUM_POINTS; i++) { > for (int j = 0; j < NON_ZERO; j++) { > adjl[i] = new node(j, adjl[i]); assert(adjl[i]); > adjr[i] = new node(j, adjr[i]); assert(adjr[i]); > } > cout << "i " << i << ": total " << (i+1) * 2 * NON_ZERO << endl; > // last output: "i 29950: total 1797060" > } > cout << "inited adjl,r[]" << endl; > > // process points[] and adjl,r[] > > // clean-up > > return 0; >} > >Hans -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Bug reporting: http://cygwin.com/bugs.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
