3 * Database load monitoring.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
23 use Psr\Log\LoggerAwareInterface
;
26 * An interface for database load monitoring
30 interface LoadMonitor
extends LoggerAwareInterface
{
32 * Construct a new LoadMonitor with a given LoadBalancer parent
34 * @param BagOStuff $sCache Server local memory cache
35 * @param BagOStuff $cCache Server local memory cache
36 * @param ILoadBalancer $parent LoadBalancer this instance serves
38 public function __construct( ILoadBalancer
$parent, BagOStuff
$sCache, BagOStuff
$cCache );
41 * Perform pre-connection load ratio adjustment.
42 * @param int[] &$loads
43 * @param string|bool $group The selected query group. Default: false
44 * @param string|bool $domain Default: false
46 public function scaleLoads( &$loads, $group = false, $domain = false );
49 * Get an estimate of replication lag (in seconds) for each server
51 * Values may be "false" if replication is too broken to estimate
53 * @param integer[] $serverIndexes
54 * @param string $domain
56 * @return array Map of (server index => float|int|bool)
58 public function getLagTimes( $serverIndexes, $domain );
61 * Clear any process and persistent cache of lag times
64 public function clearCaches();