Thijs/wiki.techinc.nl
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

objectcache: improve comments for ATTR_/QOS_ constants

Browse source 
Change-Id: Iaa5361a09e1dc559fee8eb034c9c05bc999c776e
This commit is contained in:
Aaron Schulz 2019-03-26 11:16:38 -07:00
parent 68f6d35d77
commit fce8f37378
1 changed files with 8 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

13
includes/libs/objectcache/IExpiringStore.php
View file

@ -21,7 +21,7 @@
*/
/**
* Generic base class for storage interfaces.
* Generic interface for lightweight expiring object stores.
*
* Provides convenient TTL constants.
*
@ -44,16 +44,19 @@ interface IExpiringStore {
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
// Emulation/fallback medium attribute (e.g. SQLBagOStuff)
const ATTR_EMULATION = 1;
// Quality of service constants for ATTR_EMULATION (higher means faster)
const QOS_EMULATION_SQL = 1;
// Medium attributes constants related to replica consistency
const ATTR_SYNCWRITES = 2; // SYNC_WRITES flag support
// Replica synchronization/consistency attribute of medium when SYNC_WRITES is used
const ATTR_SYNCWRITES = 2;
// Quality of service constants for ATTR_SYNCWRITES (higher means more consistent)
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;