Re: [HACKERS] Recent SIGSEGV failures in buildfarm HEAD - Mailing list pgsql-patches

From Andrew Dunstan
Subject Re: [HACKERS] Recent SIGSEGV failures in buildfarm HEAD
Date
Msg-id 459AC6A3.2000202@dunslane.net
Whole thread Raw
In response to Re: [HACKERS] Recent SIGSEGV failures in buildfarm HEAD  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: [HACKERS] Recent SIGSEGV failures in buildfarm HEAD  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-patches
Tom Lane wrote:
> Andrew Dunstan <andrew@dunslane.net> writes:
>
>> ... And then we'd need to change the regression makefile to use
>> the option, based on an environment variable a bit like MAX_CONNEXCTIONS
>> maybe.
>>
>
> Why wouldn't we just use it always?  If a regression test dumps core,
> that's going to deserve investigation.
>
>
>

Revised patch attached, doing just this. I will apply it soon unless
there are objections.

cheers

andrew

Index: doc/src/sgml/ref/pg_ctl-ref.sgml
===================================================================
RCS file: /cvsroot/pgsql/doc/src/sgml/ref/pg_ctl-ref.sgml,v
retrieving revision 1.35
diff -c -r1.35 pg_ctl-ref.sgml
*** doc/src/sgml/ref/pg_ctl-ref.sgml    2 Dec 2006 00:34:52 -0000    1.35
--- doc/src/sgml/ref/pg_ctl-ref.sgml    2 Jan 2007 20:25:01 -0000
***************
*** 29,34 ****
--- 29,35 ----
     <arg>-l <replaceable>filename</replaceable></arg>
     <arg>-o <replaceable>options</replaceable></arg>
     <arg>-p <replaceable>path</replaceable></arg>
+    <arg>-c</arg>
     <sbr>
     <command>pg_ctl</command>
     <arg choice="plain">stop</arg>
***************
*** 48,53 ****
--- 49,55 ----
     <arg>-w</arg>
     <arg>-s</arg>
     <arg>-D <replaceable>datadir</replaceable></arg>
+    <arg>-c</arg>
     <arg>-m
       <group choice="plain">
         <arg>s[mart]</arg>
***************
*** 246,251 ****
--- 248,266 ----
       </varlistentry>

       <varlistentry>
+       <term><option>-c</option></term>
+       <listitem>
+        <para>
+         Attempt to allow server crashes to produce core files, on platforms
+         where this available, by lifting any soft resource limit placed on
+         them.
+         This is useful in debugging or diagnosing problems by allowing a
+         stack trace to be obtained from a failed server process.
+        </para>
+       </listitem>
+      </varlistentry>
+
+      <varlistentry>
        <term><option>-w</option></term>
        <listitem>
         <para>
Index: src/bin/pg_ctl/pg_ctl.c
===================================================================
RCS file: /cvsroot/pgsql/src/bin/pg_ctl/pg_ctl.c,v
retrieving revision 1.74
diff -c -r1.74 pg_ctl.c
*** src/bin/pg_ctl/pg_ctl.c    12 Oct 2006 05:14:49 -0000    1.74
--- src/bin/pg_ctl/pg_ctl.c    2 Jan 2007 20:25:02 -0000
***************
*** 26,31 ****
--- 26,36 ----
  #include <sys/stat.h>
  #include <unistd.h>

+ #ifdef HAVE_SYS_RESOURCE_H
+ #include <sys/time.h>
+ #include <sys/resource.h>
+ #endif
+
  #include "libpq/pqsignal.h"
  #include "getopt_long.h"

***************
*** 90,95 ****
--- 95,103 ----
  static char *register_username = NULL;
  static char *register_password = NULL;
  static char *argv0 = NULL;
+ #if HAVE_GETRLIMIT
+ static bool allow_core_files = false;
+ #endif

  static void
  write_stderr(const char *fmt,...)
***************
*** 132,137 ****
--- 140,149 ----
  static char pid_file[MAXPGPATH];
  static char conf_file[MAXPGPATH];

+ #if HAVE_GETRLIMIT
+ static void unlimit_core_size(void);
+ #endif
+

  #if defined(WIN32) || defined(__CYGWIN__)
  static void
***************
*** 478,483 ****
--- 490,516 ----
  }


+ #if HAVE_GETRLIMIT
+ static void
+ unlimit_core_size(void)
+ {
+     struct rlimit lim;
+     getrlimit(RLIMIT_CORE,&lim);
+     if (lim.rlim_max == 0)
+     {
+             write_stderr(_("%s: cannot set core size,: disallowed by hard limit.\n"),
+                          progname);
+             return;
+     }
+     else if (lim.rlim_max == RLIM_INFINITY || lim.rlim_cur < lim.rlim_max)
+     {
+         lim.rlim_cur = lim.rlim_max;
+         setrlimit(RLIMIT_CORE,&lim);
+     }
+ }
+ #endif
+
+

  static void
  do_start(void)
***************
*** 581,586 ****
--- 614,624 ----
          postgres_path = postmaster_path;
      }

+ #if HAVE_GETRLIMIT
+     if (allow_core_files)
+         unlimit_core_size();
+ #endif
+
      exitcode = start_postmaster();
      if (exitcode != 0)
      {
***************
*** 1401,1406 ****
--- 1439,1447 ----
      printf(_("  -o OPTIONS             command line options to pass to postgres\n"
               "                         (PostgreSQL server executable)\n"));
      printf(_("  -p PATH-TO-POSTGRES    normally not necessary\n"));
+ #if HAVE_GETRLIMIT
+     printf(_("  -c, --corefiles        allow postgres to produce core files\n"));
+ #endif

      printf(_("\nOptions for stop or restart:\n"));
      printf(_("  -m SHUTDOWN-MODE   may be \"smart\", \"fast\", or \"immediate\"\n"));
***************
*** 1497,1502 ****
--- 1538,1546 ----
          {"mode", required_argument, NULL, 'm'},
          {"pgdata", required_argument, NULL, 'D'},
          {"silent", no_argument, NULL, 's'},
+ #if HAVE_GETRLIMIT
+         {"corefiles", no_argument, NULL, 'c'},
+ #endif
          {NULL, 0, NULL, 0}
      };

***************
*** 1561,1567 ****
      /* process command-line options */
      while (optind < argc)
      {
!         while ((c = getopt_long(argc, argv, "D:l:m:N:o:p:P:sU:wW", long_options, &option_index)) != -1)
          {
              switch (c)
              {
--- 1605,1611 ----
      /* process command-line options */
      while (optind < argc)
      {
!         while ((c = getopt_long(argc, argv, "cD:l:m:N:o:p:P:sU:wW", long_options, &option_index)) != -1)
          {
              switch (c)
              {
***************
*** 1632,1637 ****
--- 1676,1686 ----
                      do_wait = false;
                      wait_set = true;
                      break;
+ #if HAVE_GETRLIMIT
+                 case 'c':
+                     allow_core_files = true;
+                     break;
+ #endif
                  default:
                      /* getopt_long already issued a suitable error message */
                      do_advice();
Index: src/test/regress/pg_regress.c
===================================================================
RCS file: /cvsroot/pgsql/src/test/regress/pg_regress.c,v
retrieving revision 1.23
diff -c -r1.23 pg_regress.c
*** src/test/regress/pg_regress.c    4 Oct 2006 00:30:14 -0000    1.23
--- src/test/regress/pg_regress.c    2 Jan 2007 20:25:03 -0000
***************
*** 24,29 ****
--- 24,34 ----
  #include <signal.h>
  #include <unistd.h>

+ #ifdef HAVE_SYS_RESOURCE_H
+ #include <sys/time.h>
+ #include <sys/resource.h>
+ #endif
+
  #include "getopt_long.h"
  #include "pg_config_paths.h"

***************
*** 122,127 ****
--- 127,156 ----
     the supplied arguments. */
  __attribute__((format(printf, 2, 3)));

+ /*
+  * allow core files if possible.
+  */
+ #if HAVE_GETRLIMIT
+ static void
+ unlimit_core_size(void)
+ {
+     struct rlimit lim;
+     getrlimit(RLIMIT_CORE,&lim);
+     if (lim.rlim_max == 0)
+     {
+         fprintf(stderr,
+                 _("%s: cannot set core size,: disallowed by hard limit.\n"),
+                 progname);
+         return;
+     }
+     else if (lim.rlim_max == RLIM_INFINITY || lim.rlim_cur < lim.rlim_max)
+     {
+         lim.rlim_cur = lim.rlim_max;
+         setrlimit(RLIMIT_CORE,&lim);
+     }
+ }
+ #endif
+

  /*
   * Add an item at the end of a stringlist.
***************
*** 1459,1464 ****
--- 1488,1497 ----

      initialize_environment();

+ #if HAVE_GETRLIMIT
+     unlimit_core_size();
+ #endif
+
      if (temp_install)
      {
          /*

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