69950da666
Add more detailed QOS_* constants while at it Bug: T236412 Change-Id: Ia862c5111a3daf10a34fc78163301629228efa6b
85 lines
3.5 KiB
PHP
85 lines
3.5 KiB
PHP
<?php
|
|
/**
|
|
* Generic interface providing error code and quality-of-service constants for object stores
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
* http://www.gnu.org/copyleft/gpl.html
|
|
*
|
|
* @file
|
|
* @ingroup Cache
|
|
*/
|
|
|
|
namespace Wikimedia\LightweightObjectStore;
|
|
|
|
/**
|
|
* Generic interface providing error code and quality-of-service constants for object stores
|
|
*
|
|
* @ingroup Cache
|
|
* @since 1.35
|
|
*/
|
|
interface StorageAwareness {
|
|
/** @var int No error */
|
|
public const ERR_NONE = 0;
|
|
/** @var int No store server/medium response */
|
|
public const ERR_NO_RESPONSE = 1;
|
|
/** @var int Cannot connect to store server/medium */
|
|
public const ERR_UNREACHABLE = 2;
|
|
/** @var int Operation failed */
|
|
public const ERR_UNEXPECTED = 3;
|
|
|
|
/** @var int Emulation/fallback mode; see ATTR_EMULATION_*; higher is better */
|
|
public const ATTR_EMULATION = 1;
|
|
/** @var int Multi-DC consistency of SYNC_WRITES; see ATTR_SYNCWRITES_*; higher is better */
|
|
public const ATTR_SYNCWRITES = 2;
|
|
/** @var int Locality; see ATTR_LOCALITY_*; higher is better */
|
|
public const ATTR_LOCALITY = 3;
|
|
/** @var int Durability; see ATTR_DURABILITY_*; higher is better */
|
|
public const ATTR_DURABILITY = 4;
|
|
|
|
/** @var int Fallback disk-based SQL store */
|
|
public const QOS_EMULATION_SQL = 1;
|
|
|
|
/** @var int Asynchronous; eventually consistent or even "best effort" replicated */
|
|
public const QOS_SYNCWRITES_NONE = 1;
|
|
/** @var int Synchronous; eventually consistent or even "best effort" replicated */
|
|
public const QOS_SYNCWRITES_BE = 2;
|
|
/** @var int Synchronous with quorum; (replicas read + replicas written) > quorum */
|
|
public const QOS_SYNCWRITES_QC = 3;
|
|
/** @var int Synchronous; strict serializable */
|
|
public const QOS_SYNCWRITES_SS = 4;
|
|
|
|
/** @var int Data is replicated accross a wide area network */
|
|
public const QOS_LOCALITY_WAN = 1;
|
|
/** @var int Data is stored on servers within the local area network */
|
|
public const QOS_LOCALITY_LAN = 2;
|
|
/** @var int Data is stored in RAM owned by another process or in the local filesystem */
|
|
public const QOS_LOCALITY_SRV = 3;
|
|
/** @var int Data is stored in RAM owned by this process */
|
|
public const QOS_LOCALITY_PROC = 4;
|
|
|
|
/** @var int Data is never saved to begin with (blackhole store) */
|
|
public const QOS_DURABILITY_NONE = 1;
|
|
/** @var int Data is lost at the end of the current web request or CLI script */
|
|
public const QOS_DURABILITY_SCRIPT = 2;
|
|
/** @var int Data is lost once the service storing the data restarts */
|
|
public const QOS_DURABILITY_SERVICE = 3;
|
|
/** @var int Data is saved to disk, though without immediate fsync() */
|
|
public const QOS_DURABILITY_DISK = 4;
|
|
/** @var int Data is saved to disk via an RDBMS, usually with immediate fsync() */
|
|
public const QOS_DURABILITY_RDBMS = 5;
|
|
|
|
/** @var int Generic "unknown" value; useful for comparisons (always "good enough") */
|
|
public const QOS_UNKNOWN = INF;
|
|
}
|