Basic DB load monitor with no external dependencies Uses memcached to cache the replication lag for a short time. More...
Public Member Functions | |
| __construct (ILoadBalancer $lb, BagOStuff $srvCache, WANObjectCache $wCache, array $options=[]) | |
| Construct a new LoadMonitor with a given LoadBalancer parent. | |
| getLagTimes (array $serverIndexes, $domain) | |
| Get an estimate of replication lag (in seconds) for each server. | |
| scaleLoads (array &$weightByServer, $domain) | |
| Perform load ratio adjustment before deciding which server to use. | |
| setLogger (LoggerInterface $logger) | |
Public Attributes | |
| const | VERSION = 1 |
Protected Member Functions | |
| getServerStates (array $serverIndexes, $domain) | |
| getWeightScale ( $index, IDatabase $conn=null) | |
Protected Attributes | |
| ILoadBalancer | $parent |
| LoggerInterface | $replLogger |
| BagOStuff | $srvCache |
| WANObjectCache | $wanCache |
Private Member Functions | |
| getCacheKey (array $serverIndexes) | |
Private Attributes | |
| float | $movingAveRatio |
| Moving average ratio (e.g. | |
Detailed Description
Basic DB load monitor with no external dependencies Uses memcached to cache the replication lag for a short time.
Definition at line 36 of file LoadMonitor.php.
Constructor & Destructor Documentation
◆ __construct()
| Wikimedia\Rdbms\LoadMonitor::__construct | ( | ILoadBalancer | $lb, |
| BagOStuff | $sCache, | ||
| WANObjectCache | $wCache, | ||
| array | $options = [] ) |
Construct a new LoadMonitor with a given LoadBalancer parent.
- Parameters
-
ILoadBalancer $lb LoadBalancer this instance serves BagOStuff $sCache Local server memory cache WANObjectCache $wCache Local cluster memory cache array $options Options map
Implements Wikimedia\Rdbms\ILoadMonitor.
Reimplemented in Wikimedia\Rdbms\LoadMonitorMySQL.
Definition at line 51 of file LoadMonitor.php.
References $options, and Wikimedia\Rdbms\LoadMonitor\$srvCache.
Member Function Documentation
◆ getCacheKey()
|
private |
Definition at line 216 of file LoadMonitor.php.
Referenced by Wikimedia\Rdbms\LoadMonitor\getServerStates().
◆ getLagTimes()
| Wikimedia\Rdbms\LoadMonitor::getLagTimes | ( | array | $serverIndexes, |
| $domain ) |
Get an estimate of replication lag (in seconds) for each server.
Values may be "false" if replication is too broken to estimate
- Parameters
-
int[] $serverIndexes string $domain
- Returns
- array Map of (server index => float|int|bool)
Implements Wikimedia\Rdbms\ILoadMonitor.
Definition at line 82 of file LoadMonitor.php.
References Wikimedia\Rdbms\LoadMonitor\getServerStates().
◆ getServerStates()
|
protected |
Definition at line 88 of file LoadMonitor.php.
References Wikimedia\Rdbms\LoadMonitor\$movingAveRatio, Wikimedia\Rdbms\LoadMonitor\$srvCache, $value, Wikimedia\Rdbms\LoadMonitor\getCacheKey(), and Wikimedia\Rdbms\LoadMonitor\getWeightScale().
Referenced by Wikimedia\Rdbms\LoadMonitor\getLagTimes(), and Wikimedia\Rdbms\LoadMonitor\scaleLoads().
◆ getWeightScale()
|
protected |
- Parameters
-
int $index Server index IDatabase | null $conn Connection handle or null on connection failure
- Returns
- float
Reimplemented in Wikimedia\Rdbms\LoadMonitorMySQL.
Definition at line 212 of file LoadMonitor.php.
Referenced by Wikimedia\Rdbms\LoadMonitor\getServerStates().
◆ scaleLoads()
| Wikimedia\Rdbms\LoadMonitor::scaleLoads | ( | array & | $weightByServer, |
| $domain ) |
Perform load ratio adjustment before deciding which server to use.
- Parameters
-
int[] &$weightByServer Map of (server index => float weight) string | bool $domain
Implements Wikimedia\Rdbms\ILoadMonitor.
Definition at line 68 of file LoadMonitor.php.
References Wikimedia\Rdbms\LoadMonitor\getServerStates().
◆ setLogger()
| Wikimedia\Rdbms\LoadMonitor::setLogger | ( | LoggerInterface | $logger | ) |
Definition at line 64 of file LoadMonitor.php.
Member Data Documentation
◆ $movingAveRatio
|
private |
Moving average ratio (e.g.
0.1 for 10% weight to new weight)
Definition at line 47 of file LoadMonitor.php.
Referenced by Wikimedia\Rdbms\LoadMonitor\getServerStates().
◆ $parent
|
protected |
Definition at line 38 of file LoadMonitor.php.
◆ $replLogger
|
protected |
Definition at line 44 of file LoadMonitor.php.
◆ $srvCache
|
protected |
Definition at line 40 of file LoadMonitor.php.
Referenced by Wikimedia\Rdbms\LoadMonitor\__construct(), Wikimedia\Rdbms\LoadMonitorMySQL\__construct(), and Wikimedia\Rdbms\LoadMonitor\getServerStates().
◆ $wanCache
|
protected |
Definition at line 42 of file LoadMonitor.php.
◆ VERSION
| const Wikimedia\Rdbms\LoadMonitor::VERSION = 1 |
Definition at line 49 of file LoadMonitor.php.
The documentation for this class was generated from the following file:
- includes/libs/rdbms/loadmonitor/LoadMonitor.php
