Exemplo n.º 1
0
    /* applies oplog from "now" until endOpTime using the applier threads for initial sync*/
    void SyncTail::_applyOplogUntil(OperationContext* txn, const OpTime& endOpTime) {
        unsigned long long bytesApplied = 0;
        unsigned long long entriesApplied = 0;
        while (true) {
            OpQueue ops;
            OperationContextImpl ctx;

            while (!tryPopAndWaitForMore(&ops, getGlobalReplicationCoordinator())) {
                // nothing came back last time, so go again
                if (ops.empty()) continue;

                // Check if we reached the end
                const BSONObj currentOp = ops.back();
                const OpTime currentOpTime = currentOp["ts"]._opTime();

                // When we reach the end return this batch
                if (currentOpTime == endOpTime) {
                    break;
                }
                else if (currentOpTime > endOpTime) {
                    severe() << "Applied past expected end " << endOpTime << " to " << currentOpTime
                            << " without seeing it. Rollback?" << rsLog;
                    fassertFailedNoTrace(18693);
                }

                // apply replication batch limits
                if (ops.getSize() > replBatchLimitBytes)
                    break;
                if (ops.getDeque().size() > replBatchLimitOperations)
                    break;
            };

            if (ops.empty()) {
                severe() << "got no ops for batch...";
                fassertFailedNoTrace(18692);
            }

            const BSONObj lastOp = ops.back().getOwned();

            // Tally operation information
            bytesApplied += ops.getSize();
            entriesApplied += ops.getDeque().size();

            multiApply(ops.getDeque());
            OpTime lastOpTime = applyOpsToOplog(&ops.getDeque());

            // if the last op applied was our end, return
            if (lastOpTime == endOpTime) {
                LOG(1) << "SyncTail applied " << entriesApplied
                       << " entries (" << bytesApplied << " bytes)"
                       << " and finished at opTime " << endOpTime.toStringPretty();
                return;
            }
        } // end of while (true)
    }
    void run() {
        Client::initThread("ReplBatcher");
        OperationContextImpl txn;
        auto replCoord = ReplicationCoordinator::get(&txn);

        while (!_inShutdown.load()) {
            Timer batchTimer;

            OpQueue ops;
            // tryPopAndWaitForMore returns true when we need to end a batch early
            while (!_syncTail->tryPopAndWaitForMore(&txn, &ops) &&
                   (ops.getSize() < replBatchLimitBytes) && !_inShutdown.load()) {
                int now = batchTimer.seconds();

                // apply replication batch limits
                if (!ops.empty()) {
                    if (now > replBatchLimitSeconds)
                        break;
                    if (ops.getDeque().size() > replBatchLimitOperations)
                        break;
                }

                const int slaveDelaySecs = durationCount<Seconds>(replCoord->getSlaveDelaySecs());
                if (!ops.empty() && slaveDelaySecs > 0) {
                    const BSONObj lastOp = ops.back().raw;
                    const unsigned int opTimestampSecs = lastOp["ts"].timestamp().getSecs();

                    // Stop the batch as the lastOp is too new to be applied. If we continue
                    // on, we can get ops that are way ahead of the delay and this will
                    // make this thread sleep longer when handleSlaveDelay is called
                    // and apply ops much sooner than we like.
                    if (opTimestampSecs > static_cast<unsigned int>(time(0) - slaveDelaySecs)) {
                        break;
                    }
                }

                if (MONGO_FAIL_POINT(rsSyncApplyStop)) {
                    break;
                }

                // keep fetching more ops as long as we haven't filled up a full batch yet
            }

            // For pausing replication in tests
            while (MONGO_FAIL_POINT(rsSyncApplyStop) && !_inShutdown.load()) {
                sleepmillis(0);
            }

            stdx::unique_lock<stdx::mutex> lk(_mutex);
            while (!_ops.empty()) {
                // Block until the previous batch has been taken.
                if (_inShutdown.load())
                    return;
                _cv.wait(lk);
            }
            _ops = std::move(ops);
            _cv.notify_all();
        }
    }
Exemplo n.º 3
0
/* tail an oplog.  ok to return, will be re-called. */
void SyncTail::oplogApplication() {
    ReplicationCoordinator* replCoord = getGlobalReplicationCoordinator();
    ApplyBatchFinalizer finalizer(replCoord);

    OperationContextImpl txn;
    OpTime originalEndOpTime(getMinValid(&txn).end);

    while (!inShutdown()) {
        OpQueue ops;

        Timer batchTimer;
        int lastTimeChecked = 0;

        do {
            int now = batchTimer.seconds();

            // apply replication batch limits
            if (!ops.empty()) {
                if (now > replBatchLimitSeconds)
                    break;
                if (ops.getDeque().size() > replBatchLimitOperations)
                    break;
            }
            // occasionally check some things
            // (always checked in the first iteration of this do-while loop, because
            // ops is empty)
            if (ops.empty() || now > lastTimeChecked) {
                BackgroundSync* bgsync = BackgroundSync::get();
                if (bgsync->getInitialSyncRequestedFlag()) {
                    // got a resync command
                    return;
                }
                lastTimeChecked = now;
                // can we become secondary?
                // we have to check this before calling mgr, as we must be a secondary to
                // become primary
                tryToGoLiveAsASecondary(&txn, replCoord);
            }

            const int slaveDelaySecs = durationCount<Seconds>(replCoord->getSlaveDelaySecs());
            if (!ops.empty() && slaveDelaySecs > 0) {
                const BSONObj lastOp = ops.back();
                const unsigned int opTimestampSecs = lastOp["ts"].timestamp().getSecs();

                // Stop the batch as the lastOp is too new to be applied. If we continue
                // on, we can get ops that are way ahead of the delay and this will
                // make this thread sleep longer when handleSlaveDelay is called
                // and apply ops much sooner than we like.
                if (opTimestampSecs > static_cast<unsigned int>(time(0) - slaveDelaySecs)) {
                    break;
                }
            }

            if (MONGO_FAIL_POINT(rsSyncApplyStop)) {
                break;
            }

            // keep fetching more ops as long as we haven't filled up a full batch yet
        } while (!tryPopAndWaitForMore(&txn, &ops, replCoord) &&  // tryPopAndWaitForMore returns
                                                                  // true when we need to end a
                                                                  // batch early
                 (ops.getSize() < replBatchLimitBytes) &&
                 !inShutdown());

        // For pausing replication in tests
        while (MONGO_FAIL_POINT(rsSyncApplyStop)) {
            sleepmillis(0);
            if (inShutdown())
                return;
        }

        if (ops.empty()) {
            continue;
        }

        const BSONObj lastOp = ops.back();
        handleSlaveDelay(lastOp);

        // Set minValid to the last OpTime that needs to be applied, in this batch or from the
        // (last) failed batch, whichever is larger.
        // This will cause this node to go into RECOVERING state
        // if we should crash and restart before updating finishing.
        const OpTime start(getLastSetTimestamp(), OpTime::kUninitializedTerm);

        // Take the max of the first endOptime (if we recovered) and the end of our batch.
        const auto lastOpTime = fassertStatusOK(28773, OpTime::parseFromOplogEntry(lastOp));

        // Setting end to the max of originalEndOpTime and lastOpTime (the end of the batch)
        // ensures that we keep pushing out the point where we can become consistent
        // and allow reads. If we recover and end up doing smaller batches we must pass the
        // originalEndOpTime before we are good.
        //
        // For example:
        // batch apply, 20-40, end = 40
        // batch failure,
        // restart
        // batch apply, 20-25, end = max(25, 40) = 40
        // batch apply, 25-45, end = 45
        const OpTime end(std::max(originalEndOpTime, lastOpTime));

        // This write will not journal/checkpoint.
        setMinValid(&txn, {start, end});

        OpTime finalOpTime = multiApply(&txn, ops);
        setNewTimestamp(finalOpTime.getTimestamp());

        setMinValid(&txn, end, DurableRequirement::None);
        finalizer.record(finalOpTime);
    }
}
Exemplo n.º 4
0
/* applies oplog from "now" until endOpTime using the applier threads for initial sync*/
void InitialSync::_applyOplogUntil(OperationContext* txn, const OpTime& endOpTime) {
    unsigned long long bytesApplied = 0;
    unsigned long long entriesApplied = 0;
    while (true) {
        OpQueue ops;

        auto replCoord = repl::ReplicationCoordinator::get(txn);
        while (!tryPopAndWaitForMore(txn, &ops)) {
            // nothing came back last time, so go again
            if (ops.empty())
                continue;

            // Check if we reached the end
            const BSONObj currentOp = ops.back().raw;
            const OpTime currentOpTime =
                fassertStatusOK(28772, OpTime::parseFromOplogEntry(currentOp));

            // When we reach the end return this batch
            if (currentOpTime == endOpTime) {
                break;
            } else if (currentOpTime > endOpTime) {
                severe() << "Applied past expected end " << endOpTime << " to " << currentOpTime
                         << " without seeing it. Rollback?";
                fassertFailedNoTrace(18693);
            }

            // apply replication batch limits
            if (ops.getSize() > replBatchLimitBytes)
                break;
            if (ops.getDeque().size() > replBatchLimitOperations)
                break;
        };

        if (ops.empty()) {
            severe() << "got no ops for batch...";
            fassertFailedNoTrace(18692);
        }

        const BSONObj lastOp = ops.back().raw.getOwned();

        // Tally operation information
        bytesApplied += ops.getSize();
        entriesApplied += ops.getDeque().size();

        const OpTime lastOpTime = multiApply(txn, ops);

        replCoord->setMyLastAppliedOpTime(lastOpTime);
        setNewTimestamp(lastOpTime.getTimestamp());

        if (inShutdown()) {
            return;
        }

        // if the last op applied was our end, return
        if (lastOpTime == endOpTime) {
            LOG(1) << "SyncTail applied " << entriesApplied << " entries (" << bytesApplied
                   << " bytes) and finished at opTime " << endOpTime;
            return;
        }
    }  // end of while (true)
}
/* tail an oplog.  ok to return, will be re-called. */
void SyncTail::oplogApplication() {
    OpQueueBatcher batcher(this);

    OperationContextImpl txn;
    auto replCoord = ReplicationCoordinator::get(&txn);
    ApplyBatchFinalizer finalizer(replCoord);

    auto minValidBoundaries = getMinValid(&txn);
    OpTime originalEndOpTime(minValidBoundaries.end);
    OpTime lastWriteOpTime{replCoord->getMyLastOptime()};
    while (!inShutdown()) {
        OpQueue ops;

        do {
            if (BackgroundSync::get()->getInitialSyncRequestedFlag()) {
                // got a resync command
                return;
            }

            tryToGoLiveAsASecondary(&txn, replCoord, minValidBoundaries, lastWriteOpTime);

            // Blocks up to a second waiting for a batch to be ready to apply. If one doesn't become
            // ready in time, we'll loop again so we can do the above checks periodically.
            ops = batcher.getNextBatch(Seconds(1));
        } while (!inShutdown() && ops.empty());

        if (inShutdown())
            return;

        invariant(!ops.empty());

        const BSONObj lastOp = ops.back().raw;

        if (lastOp.isEmpty()) {
            // This means that the network thread has coalesced and we have processed all of its
            // data.
            invariant(ops.getDeque().size() == 1);
            if (replCoord->isWaitingForApplierToDrain()) {
                replCoord->signalDrainComplete(&txn);
            }
            continue;  // This wasn't a real op. Don't try to apply it.
        }

        handleSlaveDelay(lastOp);

        // Set minValid to the last OpTime that needs to be applied, in this batch or from the
        // (last) failed batch, whichever is larger.
        // This will cause this node to go into RECOVERING state
        // if we should crash and restart before updating finishing.
        const OpTime start(getLastSetTimestamp(), OpTime::kUninitializedTerm);

        // Take the max of the first endOptime (if we recovered) and the end of our batch.
        const auto lastOpTime = fassertStatusOK(28773, OpTime::parseFromOplogEntry(lastOp));

        // Setting end to the max of originalEndOpTime and lastOpTime (the end of the batch)
        // ensures that we keep pushing out the point where we can become consistent
        // and allow reads. If we recover and end up doing smaller batches we must pass the
        // originalEndOpTime before we are good.
        //
        // For example:
        // batch apply, 20-40, end = 40
        // batch failure,
        // restart
        // batch apply, 20-25, end = max(25, 40) = 40
        // batch apply, 25-45, end = 45
        const OpTime end(std::max(originalEndOpTime, lastOpTime));

        // This write will not journal/checkpoint.
        setMinValid(&txn, {start, end});

        lastWriteOpTime = multiApply(&txn, ops);
        setNewTimestamp(lastWriteOpTime.getTimestamp());

        setMinValid(&txn, end, DurableRequirement::None);
        minValidBoundaries.start = {};
        minValidBoundaries.end = end;
        finalizer.record(lastWriteOpTime);
    }
}