Name: clC74495 Date: 10/22/99


If a hotspot VM runs out of file descriptors while it is trying
to map a new chunk of memory for growing object memory,
a fatal error and coredump occurs. It would be preferrable
to treat this as an OutOfMemory exception .

In the Hotspot 1.0.1 FCS solaris sources, in os_solaris.cpp ,
there is this code:

static char* mmap_chunk( char *addr, jint size, int flags,
                         int prot = PROT_READ | PROT_WRITE | PROT_EXEC ) {
  int fd= open("/dev/zero", O_RDWR);
  if (fd < 0)
    fatal1("mmap_chunk: cannot open /dev/zero (%s)", strerror(errno));
  char *b = mmap(addr, size, prot, flags, fd, 0);
  close(fd);

  if (b == MAP_FAILED) {
    return NULL;
  }


At Gemstone, we have changed the code to be as follows. I believe
it would be a benefit to other users if this were included in
the Hotspot 2.0 source base

static char* mmap_chunk( char *addr, jint size, int flags,
                         int prot = PROT_READ | PROT_WRITE | PROT_EXEC ) {
  int fd= open("/dev/zero", O_RDWR);
  if (fd < 0) {
    // Gemstone change fatal to warning , for bug 23226
    warning("mmap_chunk: cannot open /dev/zero (%s)\n %s\n", strerror(errno),
            "May have run out of file descriptors, see /etc/sysdef | grep descript");
    return NULL;
    }
  char *b = mmap(addr, size, prot, flags, fd, 0);
  close(fd);

  if (b == MAP_FAILED) {
    return NULL;
  }
(Review ID: 96910)
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