示例#1
0
// mergeTrigger is called on a successful commit of an AdminMerge
// transaction. It recomputes stats for the receiving range.
func (r *Range) mergeTrigger(batch engine.Engine, merge *proto.MergeTrigger) error {
	if !bytes.Equal(r.Desc().StartKey, merge.UpdatedDesc.StartKey) {
		return util.Errorf("range and updated range start keys do not match: %s != %s",
			r.Desc().StartKey, merge.UpdatedDesc.StartKey)
	}

	if !r.Desc().EndKey.Less(merge.UpdatedDesc.EndKey) {
		return util.Errorf("range end key is not less than the post merge end key: %s >= %s",
			r.Desc().EndKey, merge.UpdatedDesc.EndKey)
	}

	if merge.SubsumedRaftID <= 0 {
		return util.Errorf("subsumed raft ID must be provided: %d", merge.SubsumedRaftID)
	}

	// Copy the subsumed range's response cache to the subsuming one.
	if err := r.respCache.CopyFrom(batch, merge.SubsumedRaftID); err != nil {
		return util.Errorf("unable to copy response cache to new split range: %s", err)
	}

	// Compute stats for updated range.
	now := r.rm.Clock().Timestamp()
	iter := newRangeDataIterator(&merge.UpdatedDesc, batch)
	ms, err := engine.MVCCComputeStats(iter, now.WallTime)
	iter.Close()
	if err != nil {
		return util.Errorf("unable to compute stats for the range after merge: %s", err)
	}
	if err = r.stats.SetMVCCStats(batch, ms); err != nil {
		return util.Errorf("unable to write MVCC stats: %s", err)
	}

	// Clear the timestamp cache. In the case that this replica and the
	// subsumed replica each held their respective leader leases, we
	// could merge the timestamp caches for efficiency. But it's unlikely
	// and not worth the extra logic and potential for error.
	r.Lock()
	r.tsCache.Clear(r.rm.Clock())
	r.Unlock()

	batch.Defer(func() {
		if err := r.rm.MergeRange(r, merge.UpdatedDesc.EndKey, merge.SubsumedRaftID); err != nil {
			// Our in-memory state has diverged from the on-disk state.
			log.Fatalf("failed to update store after merging range: %s", err)
		}
	})
	return nil
}
示例#2
0
// splitTrigger is called on a successful commit of an AdminSplit
// transaction. It copies the response cache for the new range and
// recomputes stats for both the existing, updated range and the new
// range.
func (r *Range) splitTrigger(batch engine.Engine, split *proto.SplitTrigger) error {
	if !bytes.Equal(r.Desc().StartKey, split.UpdatedDesc.StartKey) ||
		!bytes.Equal(r.Desc().EndKey, split.NewDesc.EndKey) {
		return util.Errorf("range does not match splits: (%s-%s) + (%s-%s) != %s",
			split.UpdatedDesc.StartKey, split.UpdatedDesc.EndKey,
			split.NewDesc.StartKey, split.NewDesc.EndKey, r)
	}

	// Copy the GC metadata.
	gcMeta, err := r.GetGCMetadata()
	if err != nil {
		return util.Errorf("unable to fetch GC metadata: %s", err)
	}
	if err := engine.MVCCPutProto(batch, nil, keys.RangeGCMetadataKey(split.NewDesc.RaftID), proto.ZeroTimestamp, nil, gcMeta); err != nil {
		return util.Errorf("unable to copy GC metadata: %s", err)
	}

	// Copy the last verification timestamp.
	verifyTS, err := r.GetLastVerificationTimestamp()
	if err != nil {
		return util.Errorf("unable to fetch last verification timestamp: %s", err)
	}
	if err := engine.MVCCPutProto(batch, nil, keys.RangeLastVerificationTimestampKey(split.NewDesc.RaftID), proto.ZeroTimestamp, nil, &verifyTS); err != nil {
		return util.Errorf("unable to copy last verification timestamp: %s", err)
	}

	// Compute stats for updated range.
	now := r.rm.Clock().Timestamp()
	iter := newRangeDataIterator(&split.UpdatedDesc, batch)
	ms, err := engine.MVCCComputeStats(iter, now.WallTime)
	iter.Close()
	if err != nil {
		return util.Errorf("unable to compute stats for updated range after split: %s", err)
	}
	if err := r.stats.SetMVCCStats(batch, ms); err != nil {
		return util.Errorf("unable to write MVCC stats: %s", err)
	}

	// Initialize the new range's response cache by copying the original's.
	if err = r.respCache.CopyInto(batch, split.NewDesc.RaftID); err != nil {
		return util.Errorf("unable to copy response cache to new split range: %s", err)
	}

	// Add the new split range to the store. This step atomically
	// updates the EndKey of the updated range and also adds the
	// new range to the store's range map.
	newRng, err := NewRange(&split.NewDesc, r.rm)
	if err != nil {
		return err
	}

	// Compute stats for new range.
	iter = newRangeDataIterator(&split.NewDesc, batch)
	ms, err = engine.MVCCComputeStats(iter, now.WallTime)
	iter.Close()
	if err != nil {
		return util.Errorf("unable to compute stats for new range after split: %s", err)
	}
	if err = newRng.stats.SetMVCCStats(batch, ms); err != nil {
		return util.Errorf("unable to write MVCC stats: %s", err)
	}

	// Copy the timestamp cache into the new range.
	r.Lock()
	r.tsCache.MergeInto(newRng.tsCache, true /* clear */)
	r.Unlock()

	batch.Defer(func() {
		if err := r.rm.SplitRange(r, newRng); err != nil {
			// Our in-memory state has diverged from the on-disk state.
			log.Fatalf("failed to update Store after split: %s", err)
		}
	})

	return nil
}