diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 8cb1eb364ae3a964080c022e1efbdb3e39b6b3ad..6afdd9c9637e2fe2814a399e6b2ce0ce16d466ab 100644
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -1,5 +1,5 @@
<!--
-$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.85 2001/09/23 21:52:36 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.86 2001/09/30 18:57:45 tgl Exp $
-->
<Chapter Id="runtime">
@@ -1218,6 +1218,26 @@ dynamic_library_path = '/usr/local/lib/postgresql:/home/my_project/lib:$libdir'
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>MAX_FILES_PER_PROCESS</varname> (<type>integer</type>)</term>
+ <listitem>
+ <para>
+ Sets the maximum number of simultaneously open files in each server
+ process. The default is 1000. The limit actually used by the code
+ is the smaller of this setting and the result of
+ <literal>sysconf(_SC_OPEN_MAX)</literal>.
+ Therefore, on systems where sysconf returns a reasonable limit,
+ you don't need to worry about this setting. But on some platforms
+ (notably, most BSD systems), sysconf returns a value that is much
+ larger than the system can really support when a large number of
+ processes all try to open that many files. If you find yourself
+ seeing <quote>Too many open files</> failures, try reducing this
+ setting.
+ This option can only be set at server start.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry>
<term><varname>MAX_FSM_RELATIONS</varname> (<type>integer</type>)</term>
<listitem>
diff --git a/src/backend/storage/file/fd.c b/src/backend/storage/file/fd.c
index a696f1fa1fb5d5a0b2b7da2deffa238650d2abc9..c2db3c8dea8328dc408ab6d9d450a761b89c1784 100644
--- a/src/backend/storage/file/fd.c
+++ b/src/backend/storage/file/fd.c
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/storage/file/fd.c,v 1.83 2001/08/04 19:42:34 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/storage/file/fd.c,v 1.84 2001/09/30 18:57:45 tgl Exp $
*
* NOTES:
*
@@ -69,7 +69,7 @@
*
* (Even though most dynamic loaders now use dlopen(3) or the
* equivalent, the OS must still open several files to perform the
- * dynamic loading. Keep this here.)
+ * dynamic loading. And stdin/stdout/stderr count too. Keep this here.)
*/
#ifndef RESERVE_FOR_LD
#define RESERVE_FOR_LD 10
@@ -87,6 +87,14 @@
#define FD_MINFREE 10
#endif
+/*
+ * A number of platforms return values for sysconf(_SC_OPEN_MAX) that are
+ * far beyond what they can really support. This GUC parameter limits what
+ * we will believe.
+ */
+int max_files_per_process = 1000;
+
+
/* Debugging.... */
#ifdef FDDEBUG
@@ -281,29 +289,46 @@ pg_nofile(void)
{
static long no_files = 0;
+ /* need do this calculation only once */
if (no_files == 0)
{
- /* need do this calculation only once */
-#ifndef HAVE_SYSCONF
- no_files = (long) NOFILE;
-#else
+ /*
+ * Ask the system what its files-per-process limit is.
+ */
+#ifdef HAVE_SYSCONF
no_files = sysconf(_SC_OPEN_MAX);
- if (no_files == -1)
+ if (no_files <= 0)
{
-/* tweak for Hurd, which does not support NOFILE */
#ifdef NOFILE
- elog(DEBUG, "pg_nofile: Unable to get _SC_OPEN_MAX using sysconf(); using %d", NOFILE);
no_files = (long) NOFILE;
#else
- elog(FATAL, "pg_nofile: Unable to get _SC_OPEN_MAX using sysconf() and NOFILE is undefined");
+ no_files = (long) max_files_per_process;
#endif
+ elog(DEBUG, "pg_nofile: sysconf(_SC_OPEN_MAX) failed; using %ld",
+ no_files);
}
+#else /* !HAVE_SYSCONF */
+#ifdef NOFILE
+ no_files = (long) NOFILE;
+#else
+ no_files = (long) max_files_per_process;
#endif
+#endif /* HAVE_SYSCONF */
+
+ /*
+ * Some platforms return hopelessly optimistic values. Apply a
+ * configurable upper limit.
+ */
+ if (no_files > (long) max_files_per_process)
+ no_files = (long) max_files_per_process;
+ /*
+ * Make sure we have enough to get by after reserving some for LD.
+ */
if ((no_files - RESERVE_FOR_LD) < FD_MINFREE)
- elog(FATAL, "pg_nofile: insufficient File Descriptors in postmaster to start backend (%ld).\n"
- " O/S allows %ld, Postmaster reserves %d, We need %d (MIN) after that.",
- no_files - RESERVE_FOR_LD, no_files, RESERVE_FOR_LD, FD_MINFREE);
+ elog(FATAL, "pg_nofile: insufficient file descriptors available to start backend.\n"
+ "\tSystem allows %ld, we need at least %d.",
+ no_files, RESERVE_FOR_LD + FD_MINFREE);
no_files -= RESERVE_FOR_LD;
}
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 6efd41c2a8e857445c101de4ff5dd4321202d778..c8a9a0afc28362e58555617945f43a6f7d40d693 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -4,7 +4,7 @@
* Support for grand unified configuration scheme, including SET
* command, configuration file, and command line options.
*
- * $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.53 2001/09/29 04:02:25 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.54 2001/09/30 18:57:45 tgl Exp $
*
* Copyright 2000 by PostgreSQL Global Development Group
* Written by Peter Eisentraut <peter_e@gmx.net>.
@@ -31,6 +31,7 @@
#include "optimizer/paths.h"
#include "optimizer/planmain.h"
#include "parser/parse_expr.h"
+#include "storage/fd.h"
#include "storage/freespace.h"
#include "storage/lock.h"
#include "storage/proc.h"
@@ -302,6 +303,9 @@ static struct config_int
{"vacuum_mem", PGC_USERSET, &VacuumMem,
8192, 1024, INT_MAX, NULL, NULL},
+ {"max_files_per_process", PGC_BACKEND, &max_files_per_process,
+ 1000, 25, INT_MAX, NULL, NULL},
+
{"debug_level", PGC_USERSET, &DebugLvl,
0, 0, 16, NULL, NULL},
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index 789f1a1d08d3911267dab58f5c50c29afe19e961..fbf555304e32f7c76c11dea529f4b85b62ffffa1 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -176,10 +176,11 @@
#
#dynamic_library_path = '$libdir'
#australian_timezones = false
-#authentication_timeout = 60 # min 1, max 600
+#authentication_timeout = 60 # min 1, max 600
#deadlock_timeout = 1000
#default_transaction_isolation = 'read committed'
-#max_expr_depth = 10000 # min 10
+#max_expr_depth = 10000 # min 10
+#max_files_per_process = 1000 # min 25
#password_encryption = false
#sql_inheritance = true
#transform_null_equals = false
diff --git a/src/include/storage/fd.h b/src/include/storage/fd.h
index f3e06978a67ed5c4825851bf905d3e3078e3a398..3526be1a1ef6ee1519bd50450106b28a00b74ab4 100644
--- a/src/include/storage/fd.h
+++ b/src/include/storage/fd.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: fd.h,v 1.30 2001/06/11 04:12:29 tgl Exp $
+ * $Id: fd.h,v 1.31 2001/09/30 18:57:45 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -43,6 +43,11 @@ typedef char *FileName;
typedef int File;
+
+/* GUC parameter */
+extern int max_files_per_process;
+
+
/*
* prototypes for functions in fd.c
*/