// ttl.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,
* 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/>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#include "mongo/pch.h"
#include "mongo/db/ttl.h"
#include "mongo/base/counter.h"
#include "mongo/db/auth/authorization_session.h"
#include "mongo/db/auth/user_name.h"
#include "mongo/db/client.h"
#include "mongo/db/commands/fsync.h"
#include "mongo/db/commands/server_status.h"
#include "mongo/db/catalog/database_holder.h"
#include "mongo/db/instance.h"
#include "mongo/db/ops/delete.h"
#include "mongo/db/repl/is_master.h"
#include "mongo/db/server_parameters.h"
#include "mongo/util/background.h"
namespace mongo {
Counter64 ttlPasses;
Counter64 ttlDeletedDocuments;
ServerStatusMetricField<Counter64> ttlPassesDisplay("ttl.passes", &ttlPasses);
ServerStatusMetricField<Counter64> ttlDeletedDocumentsDisplay("ttl.deletedDocuments", &ttlDeletedDocuments);
MONGO_EXPORT_SERVER_PARAMETER( ttlMonitorEnabled, bool, true );
class TTLMonitor : public BackgroundJob {
public:
TTLMonitor(){}
virtual ~TTLMonitor(){}
virtual string name() const { return "TTLMonitor"; }
static string secondsExpireField;
void doTTLForDB( const string& dbName ) {
bool isMaster = isMasterNs( dbName.c_str() );
vector<BSONObj> indexes;
{
auto_ptr<DBClientCursor> cursor =
db.query( dbName + ".system.indexes" ,
BSON( secondsExpireField << BSON( "$exists" << true ) ) ,
0 , /* default nToReturn */
0 , /* default nToSkip */
0 , /* default fieldsToReturn */
QueryOption_SlaveOk ); /* perform on secondaries too */
if ( cursor.get() ) {
while ( cursor->more() ) {
indexes.push_back( cursor->next().getOwned() );
}
}
}
for ( unsigned i=0; i<indexes.size(); i++ ) {
BSONObj idx = indexes[i];
BSONObj key = idx["key"].Obj();
if ( key.nFields() != 1 ) {
error() << "key for ttl index can only have 1 field" << endl;
continue;
}
if (!idx[secondsExpireField].isNumber()) {
log() << "ttl indexes require the " << secondsExpireField << " field to be "
<< "numeric but received a type of: "
<< typeName(idx[secondsExpireField].type());
continue;
}
BSONObj query;
{
BSONObjBuilder b;
b.appendDate( "$lt" , curTimeMillis64() - ( 1000 * idx[secondsExpireField].numberLong() ) );
query = BSON( key.firstElement().fieldName() << b.obj() );
}
LOG(1) << "TTL: " << key << " \t " << query << endl;
long long n = 0;
{
string ns = idx["ns"].String();
Client::WriteContext ctx( ns );
Collection* collection = ctx.ctx().db()->getCollection( ns );
if ( !collection ) {
// collection was dropped
continue;
}
NamespaceDetails* nsd = collection->details();
if ( nsd->setUserFlag( NamespaceDetails::Flag_UsePowerOf2Sizes ) ) {
// TODO: wish there was a cleaner way to do this
nsd->syncUserFlags( ns );
}
// only do deletes if on master
if ( ! isMaster ) {
continue;
}
if ( collection->getIndexCatalog()->findIndexByKeyPattern( key ) == NULL ) {
// index not finished yet
LOG(1) << " skipping index because not finished";
continue;
}
n = deleteObjects( ns , query , false , true );
ttlDeletedDocuments.increment( n );
}
LOG(1) << "\tTTL deleted: " << n << endl;
}
}
virtual void run() {
Client::initThread( name().c_str() );
cc().getAuthorizationSession()->grantInternalAuthorization();
while ( ! inShutdown() ) {
sleepsecs( 60 );
LOG(3) << "TTLMonitor thread awake" << endl;
if ( !ttlMonitorEnabled ) {
LOG(1) << "TTLMonitor is disabled" << endl;
continue;
}
if ( lockedForWriting() ) {
// note: this is not perfect as you can go into fsync+lock between
// this and actually doing the delete later
LOG(3) << " locked for writing" << endl;
continue;
}
// if part of replSet but not in a readable state (e.g. during initial sync), skip.
if ( theReplSet && !theReplSet->state().readable() )
continue;
set<string> dbs;
{
Lock::DBRead lk( "local" );
dbHolder().getAllShortNames( dbs );
}
ttlPasses.increment();
for ( set<string>::const_iterator i=dbs.begin(); i!=dbs.end(); ++i ) {
string db = *i;
try {
doTTLForDB( db );
}
catch ( DBException& e ) {
error() << "error processing ttl for db: " << db << " " << e << endl;
}
}
}
}
DBDirectClient db;
};
void startTTLBackgroundJob() {
TTLMonitor* ttl = new TTLMonitor();
ttl->go();
}
string TTLMonitor::secondsExpireField = "expireAfterSeconds";
}