MediaWiki REL1_39
StorageAwareness.php
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1<?php
25
34 public const ERR_NONE = 0;
36 public const ERR_NO_RESPONSE = 1;
38 public const ERR_UNREACHABLE = 2;
40 public const ERR_UNEXPECTED = 3;
41
43 public const ATTR_EMULATION = 1;
45 public const ATTR_DURABILITY = 2;
46
48 public const QOS_EMULATION_SQL = 1;
49
51 public const QOS_DURABILITY_NONE = 1;
53 public const QOS_DURABILITY_SCRIPT = 2;
55 public const QOS_DURABILITY_SERVICE = 3;
57 public const QOS_DURABILITY_DISK = 4;
59 public const QOS_DURABILITY_RDBMS = 5;
60
62 public const QOS_UNKNOWN = INF;
63}
Generic interface providing error code and quality-of-service constants for object stores.
const QOS_DURABILITY_SERVICE
Data is lost once the service storing the data restarts.
const QOS_DURABILITY_SCRIPT
Data is lost at the end of the current web request or CLI script.
const QOS_DURABILITY_NONE
Data is never saved to begin with (blackhole store)
const ERR_UNREACHABLE
Storage medium could not be reached to establish a connection.
const ATTR_EMULATION
Emulation/fallback mode; see QOS_EMULATION_*; higher is better.
const QOS_DURABILITY_RDBMS
Data is saved to disk and writes usually block on fsync(), like a standard RDBMS.
const ATTR_DURABILITY
Durability of writes; see QOS_DURABILITY_* (higher means stronger)
const QOS_EMULATION_SQL
Fallback disk-based SQL store.
const ERR_UNEXPECTED
Storage medium operation failed due to usage limitations or an I/O error.
const ERR_NO_RESPONSE
Storage medium failed to yield a complete response to an operation.
const QOS_UNKNOWN
Generic "unknown" value; useful for comparisons (always "good enough")
const QOS_DURABILITY_DISK
Data is saved to disk and writes do not usually block on fsync()