objectcache: rename SET_DELAY_HIGH_SEC => SET_DELAY_HIGH_MS and lower it

Change-Id: I92a1e9a713f60288eb02bdea4881d104bdf7d0f5

diff --git a/includes/libs/objectcache/WANObjectCache.php b/includes/libs/objectcache/WANObjectCache.php
index 87bccc5..ca15c0b 100644 (file)
--- a/includes/libs/objectcache/WANObjectCache.php
+++ b/includes/libs/objectcache/WANObjectCache.php
@@ -194,8 +194,8 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
        /** Tiny positive float to use when using "minTime" to assert an inequality */
        const TINY_POSTIVE = 0.000001;
 
-       /** Seconds of delay after get() where set() storms are a consideration with 'lockTSE' */
-       const SET_DELAY_HIGH_SEC = 0.1;
+       /** Milliseconds of delay after get() where set() storms are a consideration with 'lockTSE' */
+       const SET_DELAY_HIGH_MS = 50;
        /** Min millisecond set() backoff for keys in hold-off (far less than INTERIM_KEY_TTL) */
        const RECENT_SET_LOW_MS = 50;
        /** Max millisecond set() backoff for keys in hold-off (far less than INTERIM_KEY_TTL) */
@@ -1124,7 +1124,7 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
         *      stampede is worth avoiding. Note that if the key falls out of cache then concurrent
         *      threads will all run the callback on cache miss until the value is saved in cache.
         *      The only stampede protection in that case is from duplicate cache sets when the
-        *      callback takes longer than WANObjectCache::SET_DELAY_HIGH_SEC seconds; consider
+        *      callback takes longer than WANObjectCache::SET_DELAY_HIGH_MS milliseconds; consider
         *      using "busyValue" if such stampedes are a problem. Note that the higher "lockTSE" is
         *      set, the higher the worst-case staleness of returned values can be. Also note that
         *      this option does not by itself handle the case of the key simply expiring on account
@@ -1464,7 +1464,7 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
                // consistent hashing).
                if ( $lockTSE < 0 || $hasLock ) {
                        return true; // either not a priori hot or thread has the lock
-               } elseif ( $elapsed <= self::SET_DELAY_HIGH_SEC ) {
+               } elseif ( $elapsed <= self::SET_DELAY_HIGH_MS * 1e3 ) {
                        return true; // not enough time for threads to pile up
                }