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
|
/**
* Copyright (C) 2012 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,
* 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 "mongo/db/index_rebuilder.h"
#include "mongo/db/instance.h"
#include "mongo/db/pdfile.h"
namespace mongo {
IndexRebuilder indexRebuilder;
IndexRebuilder::IndexRebuilder() {}
std::string IndexRebuilder::name() const {
return "IndexRebuilder";
}
void IndexRebuilder::run() {
Client::initThread(name().c_str());
Lock::GlobalWrite lk;
Client::GodScope gs;
std::vector<std::string> dbNames;
getDatabaseNames(dbNames);
for (std::vector<std::string>::const_iterator it = dbNames.begin();
it < dbNames.end();
it++) {
checkDB(*it);
}
cc().shutdown();
}
void IndexRebuilder::checkDB(const std::string& dbName) {
const std::string systemNS = dbName + ".system.namespaces";
DBDirectClient cli;
scoped_ptr<DBClientCursor> cursor(cli.query(systemNS, Query()));
// This depends on system.namespaces not changing while we iterate
while (cursor->more()) {
BSONObj nsDoc = cursor->next();
const char* ns = nsDoc["name"].valuestrsafe();
Client::Context ctx(ns, dbpath, false);
NamespaceDetails* nsd = nsdetails(ns);
if (!nsd || !nsd->indexBuildsInProgress) {
continue;
}
log() << "Found interrupted index build on " << ns << endl;
// If the indexBuildRetry flag isn't set, just clear the inProg flag
if (!cmdLine.indexBuildRetry) {
// If we crash between unsetting the inProg flag and cleaning up the index, the
// index space will be lost.
int inProg = nsd->indexBuildsInProgress;
getDur().writingInt(nsd->indexBuildsInProgress) = 0;
for (int i = 0; i < inProg; i++) {
nsd->idx(nsd->nIndexes+i).kill_idx();
}
continue;
}
// We go from right to left building these indexes, so that indexBuildInProgress-- has
// the correct effect of "popping" an index off the list.
while (nsd->indexBuildsInProgress > 0) {
retryIndexBuild(dbName, nsd, nsd->nIndexes+nsd->indexBuildsInProgress-1);
}
}
}
void IndexRebuilder::retryIndexBuild(const std::string& dbName,
NamespaceDetails* nsd,
const int index) {
// details.info is always a valid system.indexes entry because DataFileMgr::insert journals
// creating the index doc and then insert_makeIndex durably assigns its DiskLoc to info.
// indexBuildsInProgress is set after that, so if it is set, info must be set.
IndexDetails& details = nsd->idx(index);
// First, clean up the in progress index build. Save the system.indexes entry so that we
// can add it again afterwards.
BSONObj indexObj = details.info.obj().getOwned();
// Clean up the in-progress index build
getDur().writingInt(nsd->indexBuildsInProgress) -= 1;
details.kill_idx();
// The index has now been removed from system.indexes, so the only record of it is in-
// memory. If there is a journal commit between now and when insert() rewrites the entry and
// the db crashes before the new system.indexes entry is journalled, the index will be lost
// forever. Thus, we're assuming no journaling will happen between now and the entry being
// re-written.
// We need to force a foreground index build to prevent replication from replaying an
// incompatible op (like a drop) during a yield.
// TODO: once commands can interrupt/wait for index builds, this can be removed.
indexObj = indexObj.removeField("background");
try {
const std::string ns = dbName + ".system.indexes";
theDataFileMgr.insert(ns.c_str(), indexObj.objdata(), indexObj.objsize(), false, true);
}
catch (const DBException& e) {
log() << "Rebuilding index failed: " << e.what() << " (" << e.getCode() << ")"
<< endl;
}
}
}
|
