------------------------------------------------------------
revno: 10002
revision-id: squid3@treenet.co.nz-20100612114252-aiv5gc1w4umu2kjf
parent: squid3@treenet.co.nz-20100612104620-zcj8ixv9aq9ettrt
committer: Amos Jeffries <squid3@treenet.co.nz>
branch nick: SQUID_3_1
timestamp: Sat 2010-06-12 23:42:52 +1200
message:
  Author: Henrik Nordstrom <henrik@henriknordstrom.net>
  Port from 2.7: max_filedescriptor config option
    
  Since Squid no longer really has any hardcoded filedescriptor limitations
  it makes sense to have a squid.conf directive allowing the number of
  filedescriptors to be tuned runtime. Default if unset is to obey whatever
  ulimit settings as before.
    
   * setMaxFD: figures out what to we can use for Squid_MaxFD
    
   * setSystemLimits: Configures the system limitations to match our
    expectations which might be lower than what setMaxFD finds if
    the comm loop has additional restrictions
  
   * Restrict limited select() I/O loop below FD_SETSIZE.
    
  
  AYJ:
    Henrik informs that loops using fd_set() (select and win32-select) must
    be kept below FD_SETSIZE or they can hang Squid or cause out-of-bounds
    memory errors.
  
  NP: Squid-2 does not appear to limit select() like this. May need fixing too.
------------------------------------------------------------
# Bazaar merge directive format 2 (Bazaar 0.90)
# revision_id: squid3@treenet.co.nz-20100612114252-aiv5gc1w4umu2kjf
# target_branch: http://www.squid-cache.org/bzr/squid3/trunk/
# testament_sha1: cc5b7c3179cfdc2aae57cd652ba1aaed4cb0c886
# timestamp: 2010-06-12 11:52:26 +0000
# source_branch: http://www.squid-cache.org/bzr/squid3/branches\
#   /SQUID_3_1
# base_revision_id: squid3@treenet.co.nz-20100612104620-\
#   zcj8ixv9aq9ettrt
# 
# Begin patch
=== modified file 'doc/release-notes/release-3.1.html'
--- doc/release-notes/release-3.1.html	2010-05-30 13:15:00 +0000
+++ doc/release-notes/release-3.1.html	2010-06-12 11:42:52 +0000
@@ -1000,6 +1000,9 @@
 </PRE>
 </P>
 
+<DT><B>max_filedescriptors</B><DD>
+<P>Ported from 2.7.</P>
+
 <DT><B>netdb_filename</B><DD>
 <P>
 <PRE>
@@ -1904,9 +1907,6 @@
 <P><EM>%oa</EM> tag not yet ported from 2.7</P>
 <P><EM>%sn</EM> tag not yet ported from 2.7</P>
 
-<DT><B>max_filedescriptors</B><DD>
-<P>Not yet ported from 2.7</P>
-
 <DT><B>max_stale</B><DD>
 <P>Not yet ported from 2.7</P>
 

=== modified file 'doc/release-notes/release-3.1.sgml'
--- doc/release-notes/release-3.1.sgml	2010-05-30 13:15:00 +0000
+++ doc/release-notes/release-3.1.sgml	2010-06-12 11:42:52 +0000
@@ -853,6 +853,9 @@
 	direct client address in the access log.
 	</verb>
 
+	<tag>max_filedescriptors</tag>
+	<p>Ported from 2.7.
+
 	<tag>netdb_filename</tag>
 	<verb>
 	A filename where Squid stores it's netdb state between restarts.
@@ -1691,9 +1694,6 @@
 	<p><em>%oa</em> tag not yet ported from 2.7
 	<p><em>%sn</em> tag not yet ported from 2.7
 
-	<tag>max_filedescriptors</tag>
-	<p>Not yet ported from 2.7
-
 	<tag>max_stale</tag>
 	<p>Not yet ported from 2.7
 

=== modified file 'src/cf.data.pre'
--- src/cf.data.pre	2010-06-12 10:46:20 +0000
+++ src/cf.data.pre	2010-06-12 11:42:52 +0000
@@ -6657,4 +6657,17 @@
 	Note: after changing this, Squid service must be restarted.
 DOC_END
 
+NAME: max_filedescriptors max_filedesc
+TYPE: int
+DEFAULT: 0
+LOC: Config.max_filedescriptors
+DOC_START
+	The maximum number of filedescriptors supported.
+
+	The default "0" means Squid inherits the current ulimit setting.
+
+	Note: Changing this requires a restart of Squid. Also
+	not all comm loops supports large values.
+DOC_END
+
 EOF

=== modified file 'src/main.cc'
--- src/main.cc	2010-05-29 01:39:35 +0000
+++ src/main.cc	2010-06-12 11:42:52 +0000
@@ -928,7 +928,7 @@
 #endif
 
     debugs(1, 1, "Process ID " << getpid());
-
+    setSystemLimits();
     debugs(1, 1, "With " << Squid_MaxFD << " file descriptors available");
 
 #ifdef _SQUID_MSWIN_

=== modified file 'src/protos.h'
--- src/protos.h	2010-05-14 12:40:35 +0000
+++ src/protos.h	2010-06-12 11:42:52 +0000
@@ -571,6 +571,7 @@
 SQUIDCEXTERN void writePidFile(void);
 SQUIDCEXTERN void setSocketShutdownLifetimes(int);
 SQUIDCEXTERN void setMaxFD(void);
+SQUIDCEXTERN void setSystemLimits(void);
 SQUIDCEXTERN void squid_signal(int sig, SIGHDLR *, int flags);
 SQUIDCEXTERN pid_t readPidFile(void);
 SQUIDCEXTERN void keepCapabilities(void);

=== modified file 'src/structs.h'
--- src/structs.h	2010-03-06 03:10:13 +0000
+++ src/structs.h	2010-06-12 11:42:52 +0000
@@ -618,6 +618,7 @@
 
     char *accept_filter;
     int umask;
+    int max_filedescriptors;
 
 #if USE_LOADABLE_MODULES
     wordlist *loadable_module_names;

=== modified file 'src/tools.cc'
--- src/tools.cc	2009-12-16 00:56:45 +0000
+++ src/tools.cc	2010-06-12 11:42:52 +0000
@@ -869,69 +869,82 @@
     return pid;
 }
 
+/* A little piece of glue for odd systems */
+#ifndef RLIMIT_NOFILE
+#ifdef RLIMIT_OFILE
+#define RLIMIT_NOFILE RLIMIT_OFILE
+#endif
+#endif
 
+/** Figure out the number of supported filedescriptors */
 void
 setMaxFD(void)
 {
-#if HAVE_SETRLIMIT
-    /* try to use as many file descriptors as possible */
-    /* System V uses RLIMIT_NOFILE and BSD uses RLIMIT_OFILE */
-
-    struct rlimit rl;
-#if defined(RLIMIT_NOFILE)
-
-    if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
-        debugs(50, 0, "setrlimit: RLIMIT_NOFILE: " << xstrerror());
+#if HAVE_SETRLIMIT && defined(RLIMIT_NOFILE)
+    struct rlimit rl;
+    if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
+        debugs(50, DBG_CRITICAL, "setrlimit: RLIMIT_NOFILE: " << xstrerror());
+    } else if (Config.max_filedescriptors > 0) {
+#if USE_SELECT || USE_SELECT_WIN32
+        /* select() breaks if this gets set too big */
+        if (Config.max_filedescriptors > FD_SETSIZE)
+            rl.rlim_cur = FD_SETSIZE;
+        else
+#endif
+            rl.rlim_cur = Config.max_filedescriptors;
+        if (rl.rlim_cur > rl.rlim_max)
+            rl.rlim_max = rl.rlim_cur;
+        if (setrlimit(RLIMIT_NOFILE, &rl)) {
+            debugs(50, DBG_CRITICAL, "setrlimit: RLIMIT_NOFILE: " << xstrerror());
+            getrlimit(RLIMIT_NOFILE, &rl);
+            rl.rlim_cur = rl.rlim_max;
+            if (setrlimit(RLIMIT_NOFILE, &rl)) {
+                debugs(50, DBG_CRITICAL, "setrlimit: RLIMIT_NOFILE: " << xstrerror());
+            }
+        }
+    }
+    if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
+         debugs(50, DBG_CRITICAL, "setrlimit: RLIMIT_NOFILE: " << xstrerror());
+    } else {
+        Squid_MaxFD = rl.rlim_cur;
+    }
+
+#endif /* HAVE_SETRLIMIT */
+}
+
+void
+setSystemLimits(void)
+{
+#if HAVE_SETRLIMIT && defined(RLIMIT_NOFILE) && !defined(_SQUID_CYGWIN_)
+    /* limit system filedescriptors to our own limit */
+    struct rlimit rl;
+    if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
+        debugs(50, DBG_CRITICAL, "setrlimit: RLIMIT_NOFILE: " << xstrerror());
     } else {
         rl.rlim_cur = Squid_MaxFD;
-
-        if (rl.rlim_cur > rl.rlim_max)
-            Squid_MaxFD = rl.rlim_cur = rl.rlim_max;
-
         if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
-            snprintf(tmp_error_buf, ERROR_BUF_SZ,
-                     "setrlimit: RLIMIT_NOFILE: %s", xstrerror());
-            fatal_dump(tmp_error_buf);
-        }
-    }
-
-#elif defined(RLIMIT_OFILE)
-    if (getrlimit(RLIMIT_OFILE, &rl) < 0) {
-        debugs(50, 0, "setrlimit: RLIMIT_NOFILE: " << xstrerror());
-    } else {
-        rl.rlim_cur = Squid_MaxFD;
-
-        if (rl.rlim_cur > rl.rlim_max)
-            Squid_MaxFD = rl.rlim_cur = rl.rlim_max;
-
-        if (setrlimit(RLIMIT_OFILE, &rl) < 0) {
-            snprintf(tmp_error_buf, ERROR_BUF_SZ,
-                     "setrlimit: RLIMIT_OFILE: %s", xstrerror());
-            fatal_dump(tmp_error_buf);
-        }
-    }
-
-#endif
-#else /* HAVE_SETRLIMIT */
-    debugs(21, 1, "setMaxFD: Cannot increase: setrlimit() not supported on this system");
-
+            snprintf(tmp_error_buf, ERROR_BUF_SZ, "setrlimit: RLIMIT_NOFILE: %s", xstrerror());
+            fatal_dump(tmp_error_buf);
+        }
+    }
 #endif /* HAVE_SETRLIMIT */
 
 #if HAVE_SETRLIMIT && defined(RLIMIT_DATA)
-
     if (getrlimit(RLIMIT_DATA, &rl) < 0) {
-        debugs(50, 0, "getrlimit: RLIMIT_DATA: " << xstrerror());
+        debugs(50, DBG_CRITICAL, "getrlimit: RLIMIT_DATA: " << xstrerror());
     } else if (rl.rlim_max > rl.rlim_cur) {
         rl.rlim_cur = rl.rlim_max;	/* set it to the max */
 
         if (setrlimit(RLIMIT_DATA, &rl) < 0) {
-            snprintf(tmp_error_buf, ERROR_BUF_SZ,
-                     "setrlimit: RLIMIT_DATA: %s", xstrerror());
+            snprintf(tmp_error_buf, ERROR_BUF_SZ, "setrlimit: RLIMIT_DATA: %s", xstrerror());
             fatal_dump(tmp_error_buf);
         }
     }
-
 #endif /* RLIMIT_DATA */
+    if (Config.max_filedescriptors > Squid_MaxFD) {
+        debugs(50, DBG_IMPORTANT, "NOTICE: Could not increase the number of filedescriptors");
+    }
+
 #if HAVE_SETRLIMIT && defined(RLIMIT_VMEM)
     if (getrlimit(RLIMIT_VMEM, &rl) < 0) {
         debugs(50, 0, "getrlimit: RLIMIT_VMEM: " << xstrerror());
@@ -939,12 +952,10 @@
         rl.rlim_cur = rl.rlim_max;	/* set it to the max */
 
         if (setrlimit(RLIMIT_VMEM, &rl) < 0) {
-            snprintf(tmp_error_buf, ERROR_BUF_SZ,
-                     "setrlimit: RLIMIT_VMEM: %s", xstrerror());
+            snprintf(tmp_error_buf, ERROR_BUF_SZ, "setrlimit: RLIMIT_VMEM: %s", xstrerror());
             fatal_dump(tmp_error_buf);
         }
     }
-
 #endif /* RLIMIT_VMEM */
 }