lockwiki changes

* Stop busy-waiting in lockwiki, as this could delay ikiwiki from waking up
  for up to one second. The bailout code is no longer needed.
* Remove support for unused optional wait parameter from lockwiki.

4 files changed, 18 insertions, 21 deletions

diff --git a/IkiWiki.pm b/IkiWiki.pm
index dc9b66344..d949566d8 100644
--- a/IkiWiki.pm
+++ b/IkiWiki.pm
@@ -1280,8 +1280,7 @@ sub indexlink () { #{{{
 
 my $wikilock;
 
-sub lockwiki (;$) { #{{{
-	my $wait=@_ ? shift : 1;
+sub lockwiki () { #{{{
 	# Take an exclusive lock on the wiki to prevent multiple concurrent
 	# run issues. The lock will be dropped on program exit.
 	if (! -d $config{wikistatedir}) {
@@ -1289,20 +1288,8 @@ sub lockwiki (;$) { #{{{
 	}
 	open($wikilock, '>', "$config{wikistatedir}/lockfile") ||
 		error ("cannot write to $config{wikistatedir}/lockfile: $!");
-	if (! flock($wikilock, 2 | 4)) { # LOCK_EX | LOCK_NB
-		if ($wait) {
-			debug("wiki seems to be locked, waiting for lock");
-			my $wait=600; # arbitrary, but don't hang forever to 
-			              # prevent process pileup
-			for (1..$wait) {
-				return if flock($wikilock, 2 | 4);
-				sleep 1;
-			}
-			error("wiki is locked; waited $wait seconds without lock being freed (possible stuck process or stale lock?)");
-		}
-		else {
-			return 0;
-		}
+	if (! flock($wikilock, 2)) { # LOCK_EX
+		error("failed to get lock");
 	}
 	return 1;
 } #}}}
diff --git a/debian/changelog b/debian/changelog
index dfc5de2d4..2088b07ec 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -14,6 +14,14 @@ ikiwiki (2.69) UNRELEASED; urgency=low
   * tag: Normalize tagbase so leading/trailing slashes in it don't break
     things.
   * bzr: Fix dates for recentchanges.
+  * Avoid multiple ikiwiki cgi processes piling up, eating all memory,
+    and thrashing, by making the cgi wrapper wait on a cgilock.
+    If you had to set apache's MaxClients low to avoid ikiwiki thrashing your
+    server, you can now turn it up to a high value.
+  * Stop busy-waiting in lockwiki, as this could delay ikiwiki from waking up
+    for up to one second. The bailout code is no longer needed after above
+    change.
+  * Remove support for unused optional wait parameter from lockwiki.
 
  -- Joey Hess <joeyh@debian.org>  Thu, 06 Nov 2008 16:01:00 -0500
 
diff --git a/doc/todo/avoid_thrashing.mdwn b/doc/todo/avoid_thrashing.mdwn
index 6c895e7c9..45b11d872 100644
--- a/doc/todo/avoid_thrashing.mdwn
+++ b/doc/todo/avoid_thrashing.mdwn
@@ -18,3 +18,5 @@ with no ill effects. Crank `MaxClients` up to 256? No problem..
 And there's no real reason to allow more than one ikiwiki cgi to run at a
 time. Since almost all uses of the CGI lock the index, only one can really
 be doing anything at a time. --[[Joey]]
+
+[[done]]
diff --git a/po/ikiwiki.pot b/po/ikiwiki.pot
index 34fa5e65b..8cf3853e0 100644
--- a/po/ikiwiki.pot
+++ b/po/ikiwiki.pot
@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2008-11-07 12:23-0500\n"
+"POT-Creation-Date: 2008-11-11 15:36-0500\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -910,19 +910,19 @@ msgstr ""
 
 #. translators: The first parameter is a filename, and the second is
 #. translators: a (probably not translated) error message.
-#: ../IkiWiki/Wrapper.pm:79
+#: ../IkiWiki/Wrapper.pm:93
 #, perl-format
 msgid "failed to write %s: %s"
 msgstr ""
 
 #. translators: The parameter is a C filename.
-#: ../IkiWiki/Wrapper.pm:135
+#: ../IkiWiki/Wrapper.pm:150
 #, perl-format
 msgid "failed to compile %s"
 msgstr ""
 
 #. translators: The parameter is a filename.
-#: ../IkiWiki/Wrapper.pm:155
+#: ../IkiWiki/Wrapper.pm:170
 #, perl-format
 msgid "successfully generated %s"
 msgstr ""
@@ -969,7 +969,7 @@ msgstr ""
 msgid "preprocessing loop detected on %s at depth %i"
 msgstr ""
 
-#: ../IkiWiki.pm:1685
+#: ../IkiWiki.pm:1672
 msgid "yes"
 msgstr ""