1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
/* @file manager.cpp
*/
/**
* Copyright (C) 2008 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,b
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "pch.h"
#include "rs.h"
#include "../client.h"
namespace mongo {
enum {
NOPRIMARY = -2,
SELFPRIMARY = -1
};
/* check members OTHER THAN US to see if they think they are primary */
const Member * Manager::findOtherPrimary() {
Member *m = rs->head();
Member *p = 0;
while( m ) {
if( m->state() == PRIMARY ) {
if( p ) throw "twomasters"; // our polling is asynchronous, so this is often ok.
p = m;
}
m = m->next();
}
if( p )
noteARemoteIsPrimary(p);
return p;
}
Manager::Manager(ReplSetImpl *_rs) :
task::Server("rs Manager"), rs(_rs), busyWithElectSelf(false), _primary(NOPRIMARY)
{
}
void Manager::starting() {
Client::initThread("rs Manager");
}
void Manager::noteARemoteIsPrimary(const Member *m) {
rs->_currentPrimary = m;
rs->_self->lhb() = "";
rs->_myState = RECOVERING;
}
/** called as the health threads get new results */
void Manager::msgCheckNewState() {
{
RSBase::lock lk(rs);
if( busyWithElectSelf ) return;
const Member *p = rs->currentPrimary();
const Member *p2;
try { p2 = findOtherPrimary(); }
catch(string s) {
/* two other nodes think they are primary (asynchronously polled) -- wait for things to settle down. */
log() << "replSet warning DIAG TODO 2primary" << s << rsLog;
return;
}
if( p == p2 && p ) {
return;
}
if( p2 ) {
/* someone else thinks they are primary. */
if( p == p2 ) { // already match
return;
}
if( p == 0 ) {
noteARemoteIsPrimary(p2);
return;
}
if( p != rs->_self ) {
noteARemoteIsPrimary(p2);
return;
}
/* we thought we were primary, yet now someone else thinks they are. */
if( !rs->elect.aMajoritySeemsToBeUp() ) {
noteARemoteIsPrimary(p2);
return;
}
/* ignore for now, keep thinking we are master */
return;
}
if( p ) {
/* we are already primary, and nothing significant out there has changed. */
/* todo: if !aMajoritySeemsToBeUp, relinquish */
assert( p == rs->_self );
return;
}
/* no one seems to be primary. shall we try to elect ourself? */
if( !rs->elect.aMajoritySeemsToBeUp() ) {
rs->_self->lhb() = "can't see a majority, won't consider electing self";
return;
}
rs->_self->lhb() = "";
busyWithElectSelf = true; // don't try to do further elections & such while we are already working on one.
}
try {
rs->elect.electSelf();
}
catch(RetryAfterSleepException&) {
/* we want to process new inbounds before trying this again. so we just put a checkNewstate in the queue for eval later. */
requeue();
}
catch(...) {
log() << "replSet error unexpected assertion in rs manager" << rsLog;
}
busyWithElectSelf = false;
}
}
|
