Index: trunk/phase3/includes/MessageCache.php
===================================================================
--- trunk/phase3/includes/MessageCache.php (revision 11677)
+++ trunk/phase3/includes/MessageCache.php (revision 11678)
@@ -30,6 +30,7 @@
var $mDeferred = true;
function initialise( &$memCached, $useDB, $expiry, $memcPrefix) {
+ global $wgLocalMessageCache;
$fname = 'MessageCache::initialise';
wfProfileIn( $fname );
@@ -58,13 +59,65 @@
wfProfileOut( $fname );
}
+ /**
+ * Try to load the cache from a local file
+ */
+ function loadFromLocal( $hash ) {
+ global $wgLocalMessageCache, $wgDBname;
+
+ $this->mCache = false;
+ if ( $wgLocalMessageCache === false ) {
+ return;
+ }
+
+ $filename = "$wgLocalMessageCache/messages-$wgDBname";
+
+ $file = fopen( $filename, 'r' );
+ if ( !$file ) {
+ return;
+ }
+
+ // Check to see if the file has the hash specified
+ $localHash = fread( $file, 32 );
+ if ( $hash == $localHash ) {
+ // All good, get the rest of it
+ $serialized = fread( $file, 1000000 );
+ $this->mCache = unserialize( $serialized );
+ }
+ fclose( $file );
+ }
+
/**
+ * Save the cache to a local file
+ */
+ function saveToLocal( $serialized, $hash ) {
+ global $wgLocalMessageCache, $wgDBname;
+
+ if ( $wgLocalMessageCache === false ) {
+ return;
+ }
+
+ $filename = "$wgLocalMessageCache/messages-$wgDBname";
+ wfMkdirParents( $wgLocalMessageCache, 0777 );
+
+ $file = fopen( $filename, 'w' );
+ if ( !$file ) {
+ wfDebug( "Unable to open local cache file for writing\n" );
+ return;
+ }
+
+ fwrite( $file, $hash . $serialized );
+ fclose( $file );
+ }
+
+
+ /**
* Loads messages either from memcached or the database, if not disabled
* On error, quietly switches to a fallback mode
* Returns false for a reportable error, true otherwise
*/
function load() {
- global $wgAllMessagesEn;
+ global $wgAllMessagesEn, $wgLocalMessageCache;
if ( $this->mDisable ) {
static $shownDisabled = false;
@@ -79,10 +132,34 @@
$success = true;
if ( $this->mUseCache ) {
- wfProfileIn( $fname.'-fromcache' );
- $this->mCache = $this->mMemc->get( $this->mMemcKey );
- wfProfileOut( $fname.'-fromcache' );
+ $this->mCache = false;
+ # Try local cache
+ wfProfileIn( $fname.'-fromlocal' );
+ $hash = $this->mMemc->get( "{$this->mMemcKey}-hash" );
+ if ( $hash ) {
+ $this->loadFromLocal( $hash );
+ }
+ wfProfileOut( $fname.'-fromlocal' );
+
+ # Try memcached
+ if ( !$this->mCache ) {
+ wfProfileIn( $fname.'-fromcache' );
+ $this->mCache = $this->mMemc->get( $this->mMemcKey );
+
+ # Save to local cache
+ if ( $wgLocalMessageCache !== false ) {
+ $serialized = serialize( $this->mCache );
+ if ( !$hash ) {
+ $hash = md5( $serialized );
+ $this->mMemc->set( "{$this->mMemcKey}-hash", $hash, $this->mExpiry );
+ }
+ $this->saveToLocal( $serialized, $hash );
+ }
+ wfProfileOut( $fname.'-fromcache' );
+ }
+
+
# If there's nothing in memcached, load all the messages from the database
if ( !$this->mCache ) {
wfDebug( "MessageCache::load(): loading all messages\n" );
@@ -93,6 +170,7 @@
wfProfileIn( $fname.'-load' );
$this->loadFromDB();
wfProfileOut( $fname.'-load' );
+
# Save in memcached
# Keep trying if it fails, this is kind of important
wfProfileIn( $fname.'-save' );
@@ -101,6 +179,15 @@
$i++ ) {
usleep(mt_rand(500000,1500000));
}
+
+ # Save to local cache
+ if ( $wgLocalMessageCache !== false ) {
+ $serialized = serialize( $this->mCache );
+ $hash = md5( $serialized );
+ $this->mMemc->set( "{$this->mMemcKey}-hash", $hash, $this->mExpiry );
+ $this->saveToLocal( $serialized, $hash );
+ }
+
wfProfileOut( $fname.'-save' );
if ( $i == 20 ) {
$this->mMemc->set( $this->mMemcKey.'-status', 'error', 60*5 );
@@ -199,11 +286,23 @@
}
function replace( $title, $text ) {
+ global $wgLocalMessageCache;
+
$this->lock();
$this->load();
if ( is_array( $this->mCache ) ) {
$this->mCache[$title] = $text;
$this->mMemc->set( $this->mMemcKey, $this->mCache, $this->mExpiry );
+
+ # Save to local cache
+ if ( $wgLocalMessageCache !== false ) {
+ $serialized = serialize( $this->mCache );
+ $hash = md5( $serialized );
+ $this->mMemc->set( "{$this->mMemcKey}-hash", $hash, $this->mExpiry );
+ $this->saveToLocal( $serialized, $hash );
+ }
+
+
}
$this->unlock();
}
Index: trunk/phase3/includes/DefaultSettings.php
===================================================================
--- trunk/phase3/includes/DefaultSettings.php (revision 11677)
+++ trunk/phase3/includes/DefaultSettings.php (revision 11678)
@@ -533,6 +533,10 @@
$wgMemCachedServers = array( '127.0.0.1:11000' );
$wgMemCachedDebug = false;
+/**
+ * Directory for local copy of message cache, for use in addition to memcached
+ */
+$wgLocalMessageCache = false;
# Language settings
Index: trunk/phase3/RELEASE-NOTES
===================================================================
--- trunk/phase3/RELEASE-NOTES (revision 11677)
+++ trunk/phase3/RELEASE-NOTES (revision 11678)
@@ -212,8 +212,9 @@
* Require POST for action=purge, to stop bots from purging the cache
* (bug 3817) Use localized date formats in preferences; 'no preference' option
localizable as 'datedefault' message. Tweaked lots of languages files...
+* Added local message cache feature ($wgLocalMessageCache), to reduce bandwidth
+ requirements to the memcached server.
-
=== Caveats ===
Some output, particularly involving user-supplied inline HTML, may not
