Support masking the WRITE_SYNC latency from ChronologyProtector

[lhc/web/wiklou.git] / includes / libs / objectcache / IExpiringStore.php

diff --git a/includes/libs/objectcache/IExpiringStore.php b/includes/libs/objectcache/IExpiringStore.php
index fa465c7..0e09f16 100644 (file)
--- a/includes/libs/objectcache/IExpiringStore.php
+++ b/includes/libs/objectcache/IExpiringStore.php
@@ -29,7 +29,6 @@
  * @since 1.27
  */
 interface IExpiringStore {
-
        // Constants for TTL values, in seconds
        const TTL_MINUTE = 60;
        const TTL_HOUR = 3600;
@@ -38,5 +37,22 @@ interface IExpiringStore {
        const TTL_MONTH = 2592000; // 30 * 24 * 3600
        const TTL_YEAR = 31536000; // 365 * 24 * 3600
 
+       // Shorthand process cache TTLs (useful for web requests and CLI mode)
+       const TTL_PROC_SHORT = 3; // reasonably strict cache time that last the life of quick requests
+       const TTL_PROC_LONG = 30; // loose cache time that can survive slow web requests
+
        const TTL_INDEFINITE = 0;
+
+       // Attribute and QoS constants; higher QOS values with the same prefix rank higher...
+       // Medium attributes constants related to emulation or media type
+       const ATTR_EMULATION = 1;
+       const QOS_EMULATION_SQL = 1;
+       // Medium attributes constants related to replica consistency
+       const ATTR_SYNCWRITES = 2; // SYNC_WRITES flag support
+       const QOS_SYNCWRITES_NONE = 1; // replication only supports eventual consistency or less
+       const QOS_SYNCWRITES_BE = 2; // best effort synchronous with limited retries
+       const QOS_SYNCWRITES_QC = 3; // write quorum applied directly to state machines where R+W > N
+       const QOS_SYNCWRITES_SS = 4; // strict-serializable, nodes refuse reads if possible stale
+       // Generic "unknown" value that is useful for comparisons (e.g. always good enough)
+       const QOS_UNKNOWN = INF;
 }