X-Git-Url: https://git.heureux-cyclage.org/?p=lhc%2Fweb%2Fwiklou.git;a=blobdiff_plain;f=includes%2Flibs%2Fobjectcache%2FWANObjectCache.php;h=658b225b44fed3b49cadbdd852ab362871e94741;hp=d9398196f5d4d9d03c45f0f0ee4a55a3d62f1ae8;hb=631e8695b15412ec16c31623cbd6e5aa3d6efb1e;hpb=a9f438227050c1fac6efe91fa8ff38947ae7c089

diff --git a/includes/libs/objectcache/WANObjectCache.php b/includes/libs/objectcache/WANObjectCache.php
index d9398196f5..658b225b44 100644
--- a/includes/libs/objectcache/WANObjectCache.php
+++ b/includes/libs/objectcache/WANObjectCache.php
@@ -118,6 +118,9 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 	/** @var int Key fetched */
 	private $warmupKeyMisses = 0;
 
+	/** @var float|null */
+	private $wallClockOverride;
+
 	/** Max time expected to pass between delete() and DB commit finishing */
 	const MAX_COMMIT_DELAY = 3;
 	/** Max replication+snapshot lag before applying TTL_LAGGED or disallowing set() */
@@ -134,8 +137,6 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 	const LOCK_TTL = 10;
 	/** Default remaining TTL at which to consider pre-emptive regeneration */
 	const LOW_TTL = 30;
-	/** Default time-since-expiry on a miss that makes a key "hot" */
-	const LOCK_TSE = 1;
 
 	/** Never consider performing "popularity" refreshes until a key reaches this age */
 	const AGE_NEW = 60;
@@ -284,7 +285,8 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 	 * (e.g. the default REPEATABLE-READ in innoDB). Even for mutable data, that
 	 * isolation can largely be maintained by doing the following:
 	 *   - a) Calling delete() on entity change *and* creation, before DB commit
-	 *   - b) Keeping transaction duration shorter than delete() hold-off TTL
+	 *   - b) Keeping transaction duration shorter than the delete() hold-off TTL
+	 *   - c) Disabling interim key caching via useInterimHoldOffCaching() before get() calls
 	 *
 	 * However, pre-snapshot values might still be seen if an update was made
 	 * in a remote datacenter but the purge from delete() didn't relay yet.
@@ -518,18 +520,18 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 			// Case B: any long-running transaction; ignore this set()
 			} elseif ( $age > self::MAX_READ_LAG ) {
 				$this->logger->info( 'Rejected set() for {cachekey} due to snapshot lag.',
-					[ 'cachekey' => $key ] );
+					[ 'cachekey' => $key, 'lag' => $lag, 'age' => $age ] );
 
 				return true; // no-op the write for being unsafe
 			// Case C: high replication lag; lower TTL instead of ignoring all set()s
 			} elseif ( $lag === false || $lag > self::MAX_READ_LAG ) {
 				$ttl = $ttl ? min( $ttl, self::TTL_LAGGED ) : self::TTL_LAGGED;
 				$this->logger->warning( 'Lowered set() TTL for {cachekey} due to replication lag.',
-					[ 'cachekey' => $key ] );
+					[ 'cachekey' => $key, 'lag' => $lag, 'age' => $age ] );
 			// Case D: medium length request with medium replication lag; ignore this set()
 			} else {
 				$this->logger->info( 'Rejected set() for {cachekey} due to high read lag.',
-					[ 'cachekey' => $key ] );
+					[ 'cachekey' => $key, 'lag' => $lag, 'age' => $age ] );
 
 				return true; // no-op the write for being unsafe
 			}
@@ -1537,7 +1539,7 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 	}
 
 	/**
-	 * Locally set a key to expire soon if it is stale based on $purgeTimestamp
+	 * Set a key to soon expire in the local cluster if it pre-dates $purgeTimestamp
 	 *
 	 * This sets stale keys' time-to-live at HOLDOFF_TTL seconds, which both avoids
 	 * broadcasting in mcrouter setups and also avoids races with new tombstones.
@@ -1569,7 +1571,7 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 	}
 
 	/**
-	 * Locally set a "check" key to expire soon if it is stale based on $purgeTimestamp
+	 * Set a "check" key to soon expire in the local cluster if it pre-dates $purgeTimestamp
 	 *
 	 * @param string $key Cache key
 	 * @param int $purgeTimestamp UNIX timestamp of purge
@@ -1582,7 +1584,7 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 		if ( $purge && $purge[self::FLD_TIME] < $purgeTimestamp ) {
 			$isStale = true;
 			$this->logger->warning( "Reaping stale check key '$key'." );
-			$ok = $this->cache->changeTTL( self::TIME_KEY_PREFIX . $key, 1 );
+			$ok = $this->cache->changeTTL( self::TIME_KEY_PREFIX . $key, self::TTL_SECOND );
 			if ( !$ok ) {
 				$this->logger->error( "Could not complete reap of check key '$key'." );
 			}
@@ -1825,7 +1827,7 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 				'cmd' => 'set',
 				'key' => $key,
 				'val' => 'PURGED:$UNIXTIME$:' . (int)$holdoff,
-				'ttl' => max( $ttl, 1 ),
+				'ttl' => max( $ttl, self::TTL_SECOND ),
 				'sbt' => true, // substitute $UNIXTIME$ with actual microtime
 			] );
 
@@ -2065,14 +2067,6 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 		return isset( $parts[1] ) ? $parts[1] : $parts[0]; // sanity
 	}
 
-	/**
-	 * @return float UNIX timestamp
-	 * @codeCoverageIgnore
-	 */
-	protected function getCurrentTime() {
-		return microtime( true );
-	}
-
 	/**
 	 * @param string $value Wrapped value like "PURGED:<timestamp>:<holdoff>"
 	 * @return array|bool Array containing a UNIX timestamp (float) and holdoff period (integer),
@@ -2174,4 +2168,21 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
 
 		return $warmupCache;
 	}
+
+	/**
+	 * @return float UNIX timestamp
+	 * @codeCoverageIgnore
+	 */
+	protected function getCurrentTime() {
+		return $this->wallClockOverride ?: microtime( true );
+	}
+
+	/**
+	 * @param float|null &$time Mock UNIX timestamp for testing
+	 * @codeCoverageIgnore
+	 */
+	public function setMockTime( &$time ) {
+		$this->wallClockOverride =& $time;
+		$this->cache->setMockTime( $time );
+	}
 }