|
1
|
|
|
<?php |
|
2
|
|
|
/** |
|
3
|
|
|
* This program is free software; you can redistribute it and/or modify |
|
4
|
|
|
* it under the terms of the GNU General Public License as published by |
|
5
|
|
|
* the Free Software Foundation; either version 2 of the License, or |
|
6
|
|
|
* (at your option) any later version. |
|
7
|
|
|
* |
|
8
|
|
|
* This program is distributed in the hope that it will be useful, |
|
9
|
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
|
10
|
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
|
11
|
|
|
* GNU General Public License for more details. |
|
12
|
|
|
* |
|
13
|
|
|
* You should have received a copy of the GNU General Public License along |
|
14
|
|
|
* with this program; if not, write to the Free Software Foundation, Inc., |
|
15
|
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. |
|
16
|
|
|
* http://www.gnu.org/copyleft/gpl.html |
|
17
|
|
|
* |
|
18
|
|
|
* @file |
|
19
|
|
|
* @ingroup Database |
|
20
|
|
|
*/ |
|
21
|
|
|
|
|
22
|
|
|
/** |
|
23
|
|
|
* Basic MySQL load monitor with no external dependencies |
|
24
|
|
|
* Uses memcached to cache the replication lag for a short time |
|
25
|
|
|
* |
|
26
|
|
|
* @ingroup Database |
|
27
|
|
|
*/ |
|
28
|
|
|
class LoadMonitorMySQL extends LoadMonitor { |
|
29
|
|
|
/** @var float What buffer pool use ratio counts as "warm" (e.g. 0.5 for 50% usage) */ |
|
30
|
|
|
private $warmCacheRatio; |
|
31
|
|
|
|
|
32
|
|
|
public function __construct( |
|
33
|
|
|
ILoadBalancer $lb, BagOStuff $srvCache, BagOStuff $cache, array $options = [] |
|
34
|
|
|
) { |
|
35
|
|
|
parent::__construct( $lb, $srvCache, $cache, $options ); |
|
36
|
|
|
|
|
37
|
|
|
$this->warmCacheRatio = isset( $options['warmCacheRatio'] ) |
|
38
|
|
|
? $options['warmCacheRatio'] |
|
39
|
|
|
: 0.0; |
|
40
|
|
|
} |
|
41
|
|
|
|
|
42
|
|
|
protected function getWeightScale( $index, IDatabase $conn = null ) { |
|
43
|
|
|
if ( !$conn ) { |
|
44
|
|
|
return 0.0; |
|
45
|
|
|
} |
|
46
|
|
|
|
|
47
|
|
|
$weight = 1.0; |
|
48
|
|
|
if ( $this->warmCacheRatio > 0 ) { |
|
49
|
|
|
$res = $conn->query( 'SHOW STATUS', false ); |
|
50
|
|
|
$s = $res ? $conn->fetchObject( $res ) : false; |
|
|
|
|
|
|
51
|
|
|
if ( $s === false ) { |
|
52
|
|
|
$host = $this->parent->getServerName( $index ); |
|
53
|
|
|
$this->replLogger->error( __METHOD__ . ": could not get status for $host" ); |
|
54
|
|
|
} else { |
|
55
|
|
|
// https://dev.mysql.com/doc/refman/5.7/en/server-status-variables.html |
|
56
|
|
|
if ( $s->Innodb_buffer_pool_pages_total > 0 ) { |
|
57
|
|
|
$ratio = $s->Innodb_buffer_pool_pages_data / $s->Innodb_buffer_pool_pages_total; |
|
58
|
|
|
} elseif ( $s->Qcache_total_blocks > 0 ) { |
|
59
|
|
|
$ratio = 1.0 - $s->Qcache_free_blocks / $s->Qcache_total_blocks; |
|
60
|
|
|
} else { |
|
61
|
|
|
$ratio = 1.0; |
|
62
|
|
|
} |
|
63
|
|
|
// Stop caring once $ratio >= $this->warmCacheRatio |
|
64
|
|
|
$weight *= min( $ratio / $this->warmCacheRatio, 1.0 ); |
|
65
|
|
|
} |
|
66
|
|
|
} |
|
67
|
|
|
|
|
68
|
|
|
return $weight; |
|
69
|
|
|
} |
|
70
|
|
|
} |
|
71
|
|
|
|
wikimedia /
mediawiki
If a method or function can return multiple different values and unless you are sure that you only can receive a single value in this context, we recommend to add an additional type check:
If this a common case that PHP Analyzer should handle natively, please let us know by opening an issue.