Re: [HACKERS] Too-many-files errors on OS X

[Larry Rosenman]

--On Sunday, February 22, 2004 23:00:31 -0500 Tom Lane <[EMAIL PROTECTED]> wrote:

Kevin Brown <[EMAIL PROTECTED]> writes:

I wasn't able to test on HP-UX

I get the same result on HPUX, after whacking the test program around
a bit: no change in the number of files we can open.  Confirmations on
other platforms please, anyone?

For anyone else who has problems getting it to compile, try copying
the relevant version of pg_dlopen from src/backend/port/dynloader/.
I attach the code I actually ran on HPUX.

regards, tom lane

On FreeBSD 5:

$ ./eatfds3 /usr/local/lib/libpq.so /usr/lib/libm.so
dup() failed: Too many open files
Was able to use 7146 file descriptors
dup() failed: Too many open files
Was able to use 7146 file descriptors after opening 2 shared libs
$

On UnixWare 7.1.4:
$ ./eatfds3 /usr/lib/libpq.so.3 /usr/lib/libm.so.1
dup() failed: Too many open files
Was able to use 2045 file descriptors
dup() failed: Too many open files
Was able to use 2045 file descriptors after opening 2 shared libs
$

I had to hack on the code some more for FreeBSD:
(the realloc call needed the multiplication).  I ran this same code
on UnixWare.

$ cat eatfds3.c
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <dlfcn.h>
// these seem to be needed on HPUX:
//#include <a.out.h>
//#include <dl.h>

int *fd;
int size = 3072;

void *
pg_dlopen(char *filename)
{
/*
* Use BIND_IMMEDIATE so that undefined symbols cause a failure return
* from shl_load(), rather than an abort() later on when we attempt to
* call the library!
*/
caddr_t handle = dlopen(filename,
RTLD_LAZY);

       return (void *) handle;
}

int eatallfds(void) {
       int i = 0;
       int j, myfd;

while (1) {
myfd = dup(0);
if (myfd < 0) {
fprintf (stderr, "dup() failed: %s\n", strerror(errno));
break;
}
if (i >= size) {
size *= 2;
fd = realloc(fd, size * sizeof(*fd));
if (fd == NULL) {
fprintf (stderr, "Can't allocate: %s\n",
strerror(errno));
fprintf (stderr, "Had used %d descriptors\n",
i);
exit(1);
}
}
fd[i++] = myfd;
}
for (j = 0 ; j < i ; ++j) {
close(fd[j]);
}
return i;
}

int main (int argc, char *argv[]) {
       int n, na;
       int i;
       void *addr;

       size = 3072;
       fd = malloc((size + 1) * sizeof(*fd));
       if (fd == NULL) {
               fprintf (stderr, "Can't allocate: %s\n", strerror(errno));
               return 1;
       }
       n = eatallfds();
       printf ("Was able to use %d file descriptors\n", n);

na = 0;
for (i = 1 ; i < argc ; ++i) {
addr = pg_dlopen(argv[i]);
if (addr != NULL) na++;
}
n = eatallfds();
printf ("Was able to use %d file descriptors after opening %d shared libs\n", n, na);
return 0;
}

$

--
Larry Rosenman                     http://www.lerctr.org/~ler
Phone: +1 972-414-9812                 E-Mail: [EMAIL PROTECTED]
US Mail: 1905 Steamboat Springs Drive, Garland, TX 75044-6749

pgp00000.pgp
Description: PGP signature