Failure to build libjava on 512MB machine
Gerald Pfeifer
gerald@pfeifer.com
Thu Feb 1 21:19:00 GMT 2007
On Wed, 31 Jan 2007, Andrew Haley wrote:
> Can you tell us a bit more about the config? It really shouldn't be
> failing to compile this program.
The tester where this problem first surfaced as a 32-bit Athlon machine,
with 512MB main memory and 1GB swap. The machine runs FreeBSD 5.4.
I agree with your intuition that even if the machines is swapping heavily,
this amount of virtual memory (1.5GB) should suffice.
However, a bit of investigations makes me believe that, at least in the
default configuration, FreeBSD 5.4 will refuse to allocate more memory to
a single process than the system has main memory.
At least this is what the output of the following quick test program I
hacked indicates:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#define MB 1024*1024
main() {
for(int i=1; i <= 600; i++) {
printf("%dMB ",i); fflush(stdout);
char *p=(char*)malloc(MB);
if( p == NULL ) {
printf("\nCrap!\n");
return 1;
}
}
}
After 512MB, the output I get is
510MB
511MB
512MB
Crap!
while, at the same time, a GCC bootstrap is nicely proceeding on the
same machine. I do not know how many other system may behave similarly,
but at least this explains my (unexpected) bootstrap failures.
Gerald
More information about the Gcc
mailing list