Malloc and osx update build 9G55

Question

Hi guys.
I wrote a little app in c using xcode tools; it's my graduation project, and it consists in simulating a p2p network.
Well, last week I ran the app with 1000, 10.000, 20.000, 80.000 and 150.000 nodes, and it worked perfectly.
Now I have to run it again but, after updating the o.s. with the last update of ilife and media browser provided by apple via software update, it no longer works.
Malloc fails to build the structure with 150.000 nodes (but it works perfectly building 1.000->80.000 nodes).
I tried on another mac with my same configuration (10.5.6, last update, xcode 3.2.1 and so on) and the problem persists the same way.
On a gentoo with gcc 4.1.2 it works perfectly. same source code.
Any idea??
Thanks.
Message was edited by: Mailor

Answer 1

etresoft wrote:
I think you're going to have to post some code. Just because it worked last week and on Linux doesn't mean that it was correct. Typically when something like this happens the code actually isn't correct. Linux is notorious for getting incorrect code to work. That is why it is never as easy as it appears to port from Linux to Mac. The first step is always fixing bugs that Linux ignored.
code wrote:
struct tabellanodo{
int idnodo[CARD_MAX_TABELLAAMICI], card_tabella;
int confidenza[CARDMAX_TABELLAAMICI][2];
int interessicomuni[CARD_MAX_TABELLA_AMICI][NUM_INTERESSI_COMUNIMAX];
int cardinteressi_comuni[CARD_MAX_TABELLAAMICI][2];
struct infonodo{
int numeroconnessioni_nodimaliziosi;
int nodimaliziosi_sottosmin;
int nodimaliziosi_soprasmin;
double numero_richieste;
int numerorisposte_maliziosericevute;
int numeronodi_non_maliz_sottosmin;
struct _nodo{
int malizioso; // 0: non malizioso; 1: malizioso
int id_nodo, card_intressi,famoso;
int indiceinteressi[INTERESSITOTALI];
int nodibannati[CARD_MAX_TABELLABANNATI];
int cardnodibannati;
those structures are allocated this way:
net = malloc((num_nodi+1)*sizeof(nodo));
tabella = malloc((numnodi+1)*sizeof(tabellanodo));
tabellainfonodo = malloc((numnodi+1)*sizeof(infonodo));
there are other 2 malloc:
nodimaliztrovati = malloc((num_nodi+1)*sizeof(int));
nodimaliz_sottosmin = malloc((num_nodi+1)*sizeof(int));
num_nodi is equal to 150000.
#define CARDMAX_TABELLAAMICI 100
#define CARDMAX_TABELLABANNATI 100
#define NODI_SCONOSCIUTI 20
#define INTERESSI_TOTALI 70
#define NUMINTERESSI_COMUNIMAX 40
This is from the file system. How big are your files? What architecture are you using? What API are you using for your files? MacOS X likes to use mmap when opening files. This is great for small files but becomes horribly slow for large files. If the files are big enough, > 2 Gig in this case, it may not work at all.
i do NOT open ANY file running the program. there's no way it tries to access the disk nor writing nor reading.
the only operations it executes are those said before.
note: defining CARDMAX_TABELLAAMICI to 80, makes it work fine. 90 breaks it as like as 100, but 80 doesn't.
Thanks
Message was edited by: Mailor