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/**
* 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.
*/
#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kReplication
#include "mongo/platform/basic.h"
#include "mongo/db/repl/rs_sync.h"
#include <vector>
#include "third_party/murmurhash3/MurmurHash3.h"
#include "mongo/base/counter.h"
#include "mongo/db/client.h"
#include "mongo/db/commands/fsync.h"
#include "mongo/db/commands/server_status.h"
#include "mongo/db/curop.h"
#include "mongo/db/concurrency/d_concurrency.h"
#include "mongo/db/namespace_string.h"
#include "mongo/db/repl/bgsync.h"
#include "mongo/db/repl/member.h"
#include "mongo/db/repl/minvalid.h"
#include "mongo/db/repl/oplog.h"
#include "mongo/db/repl/repl_settings.h"
#include "mongo/db/repl/repl_coordinator_global.h"
#include "mongo/db/repl/rs.h"
#include "mongo/db/repl/rs_initialsync.h"
#include "mongo/db/repl/rslog.h"
#include "mongo/db/repl/sync_tail.h"
#include "mongo/db/server_parameters.h"
#include "mongo/db/stats/timer_stats.h"
#include "mongo/db/operation_context_impl.h"
#include "mongo/db/storage_options.h"
#include "mongo/util/exit.h"
#include "mongo/util/fail_point_service.h"
#include "mongo/util/log.h"
namespace mongo {
namespace repl {
Status ReplSetImpl::forceSyncFrom(const string& host, BSONObjBuilder* result) {
lock lk(this);
// initial sanity check
if (iAmArbiterOnly()) {
return Status(ErrorCodes::NotSecondary, "arbiters don't sync");
}
if (box.getState().primary()) {
return Status(ErrorCodes::NotSecondary, "primaries don't sync");
}
if (_self != NULL && host == _self->fullName()) {
return Status(ErrorCodes::InvalidOptions, "I cannot sync from myself");
}
// find the member we want to sync from
Member *newTarget = 0;
for (Member *m = _members.head(); m; m = m->next()) {
if (m->fullName() == host) {
newTarget = m;
break;
}
}
// do some more sanity checks
if (!newTarget) {
// this will also catch if someone tries to sync a member from itself, as _self is not
// included in the _members list.
return Status(ErrorCodes::NodeNotFound, "could not find member in replica set");
}
if (newTarget->config().arbiterOnly) {
return Status(ErrorCodes::InvalidOptions, "I cannot sync from an arbiter");
}
if (!newTarget->config().buildIndexes && myConfig().buildIndexes) {
return Status(ErrorCodes::InvalidOptions,
"I cannot sync from a member who does not build indexes");
}
if (newTarget->hbinfo().authIssue) {
return Status(ErrorCodes::Unauthorized,
"not authorized to communicate with " + newTarget->fullName());
}
if (newTarget->hbinfo().health == 0) {
return Status(ErrorCodes::HostUnreachable, "I cannot reach the requested member");
}
if (newTarget->hbinfo().opTime.getSecs()+10 < lastOpTimeWritten.getSecs()) {
log() << "attempting to sync from " << newTarget->fullName()
<< ", but its latest opTime is " << newTarget->hbinfo().opTime.getSecs()
<< " and ours is " << lastOpTimeWritten.getSecs() << " so this may not work"
<< rsLog;
result->append("warning", "requested member is more than 10 seconds behind us");
// not returning false, just warning
}
// record the previous member we were syncing from
const HostAndPort prev = BackgroundSync::get()->getSyncTarget();
if (!prev.empty()) {
result->append("prevSyncTarget", prev.toString());
}
// finally, set the new target
_forceSyncTarget = newTarget;
return Status::OK();
}
bool ReplSetImpl::gotForceSync() {
lock lk(this);
return _forceSyncTarget != 0;
}
bool ReplSetImpl::shouldChangeSyncTarget(const HostAndPort& currentTarget) {
lock lk(this);
OpTime targetOpTime = findByName(currentTarget.toString())->hbinfo().opTime;
for (Member *m = _members.head(); m; m = m->next()) {
if (m->syncable() &&
targetOpTime.getSecs()+maxSyncSourceLagSecs < m->hbinfo().opTime.getSecs()) {
log() << "changing sync target because current sync target's most recent OpTime is "
<< targetOpTime.toStringPretty() << " which is more than "
<< maxSyncSourceLagSecs << " seconds behind member " << m->fullName()
<< " whose most recent OpTime is " << m->hbinfo().opTime.getSecs();
return true;
}
}
if (gotForceSync()) {
return true;
}
return false;
}
void ReplSetImpl::clearVetoes() {
lock lk(this);
_veto.clear();
}
void runSyncThread() {
Client::initThread("rsSync");
replLocalAuth();
ReplicationCoordinator* replCoord = getGlobalReplicationCoordinator();
// Set initial indexPrefetch setting
std::string& prefetch = replCoord->getSettings().rsIndexPrefetch;
if (!prefetch.empty()) {
BackgroundSync::IndexPrefetchConfig prefetchConfig = BackgroundSync::PREFETCH_ALL;
if (prefetch == "none")
prefetchConfig = BackgroundSync::PREFETCH_NONE;
else if (prefetch == "_id_only")
prefetchConfig = BackgroundSync::PREFETCH_ID_ONLY;
else if (prefetch == "all")
prefetchConfig = BackgroundSync::PREFETCH_ALL;
else {
warning() << "unrecognized indexPrefetch setting " << prefetch << ", defaulting "
<< "to \"all\"";
}
BackgroundSync::get()->setIndexPrefetchConfig(prefetchConfig);
}
while (!inShutdown()) {
// After a reconfig, we may not be in the replica set anymore, so
// check that we are in the set (and not an arbiter) before
// trying to sync with other replicas.
// TODO(spencer): Use a condition variable to await loading a config
if (replCoord->getReplicationMode() != ReplicationCoordinator::modeReplSet) {
log() << "replSet warning did not receive a valid config yet, sleeping 5 seconds "
<< rsLog;
sleepsecs(5);
continue;
}
const MemberState memberState = replCoord->getCurrentMemberState();
if (replCoord->getCurrentMemberState().arbiter()) {
break;
}
try {
if (memberState.primary() && !replCoord->isWaitingForApplierToDrain()) {
sleepsecs(1);
continue;
}
bool initialSyncRequested = BackgroundSync::get()->getInitialSyncRequestedFlag();
// Check criteria for doing an initial sync:
// 1. If the oplog is empty, do an initial sync
// 2. If minValid has _initialSyncFlag set, do an initial sync
// 3. If initialSyncRequested is true
if (getGlobalReplicationCoordinator()->getMyLastOptime().isNull() ||
getInitialSyncFlag() ||
initialSyncRequested) {
syncDoInitialSync();
continue; // start from top again in case sync failed.
}
replCoord->setFollowerMode(MemberState::RS_RECOVERING);
/* we have some data. continue tailing. */
SyncTail tail(BackgroundSync::get(), multiSyncApply);
tail.oplogApplication();
}
catch(const DBException& e) {
log() << "Received exception while syncing: " << e.toString();
sleepsecs(10);
}
catch(...) {
sethbmsg("unexpected exception in syncThread()");
// TODO : SET NOT SECONDARY here?
sleepsecs(60);
}
}
cc().shutdown();
}
} // namespace repl
} // namespace mongo
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