// RangeLookup dispatches an RangeLookup request for the given
// metadata key to the replicas of the given range. Note that we allow
// inconsistent reads when doing range lookups for efficiency. Getting
// stale data is not a correctness problem but instead may
// infrequently result in additional latency as additional range
// lookups may be required. Note also that rangeLookup bypasses the
// DistSender's Send() method, so there is no error inspection and
// retry logic here; this is not an issue since the lookup performs a
// single inconsistent read only.
func (ds *DistSender) RangeLookup(key roachpb.RKey, desc *roachpb.RangeDescriptor, considerIntents, useReverseScan bool) ([]roachpb.RangeDescriptor, *roachpb.Error) {
ba := roachpb.BatchRequest{}
ba.ReadConsistency = roachpb.INCONSISTENT
ba.Add(&roachpb.RangeLookupRequest{
Span: roachpb.Span{
// We can interpret the RKey as a Key here since it's a metadata
// lookup; those are never local.
Key: key.AsRawKey(),
},
MaxRanges: ds.rangeLookupMaxRanges,
ConsiderIntents: considerIntents,
Reverse: useReverseScan,
})
replicas := newReplicaSlice(ds.gossip, desc)
// TODO(tschottdorf) consider a Trace here, potentially that of the request
// that had the cache miss and waits for the result.
br, err := ds.sendRPC(nil /* Trace */, desc.RangeID, replicas, rpc.OrderRandom, ba)
if err != nil {
return nil, err
}
if br.Error != nil {
return nil, br.Error
}
return br.Responses[0].GetInner().(*roachpb.RangeLookupResponse).Ranges, nil
}
// RangeLookup implements the RangeDescriptorDB interface.
// RangeLookup dispatches a RangeLookup request for the given metadata
// key to the replicas of the given range. Note that we allow
// inconsistent reads when doing range lookups for efficiency. Getting
// stale data is not a correctness problem but instead may
// infrequently result in additional latency as additional range
// lookups may be required. Note also that rangeLookup bypasses the
// DistSender's Send() method, so there is no error inspection and
// retry logic here; this is not an issue since the lookup performs a
// single inconsistent read only.
func (ds *DistSender) RangeLookup(
key roachpb.RKey, desc *roachpb.RangeDescriptor, considerIntents, useReverseScan bool,
) ([]roachpb.RangeDescriptor, []roachpb.RangeDescriptor, *roachpb.Error) {
ba := roachpb.BatchRequest{}
ba.ReadConsistency = roachpb.INCONSISTENT
ba.Add(&roachpb.RangeLookupRequest{
Span: roachpb.Span{
// We can interpret the RKey as a Key here since it's a metadata
// lookup; those are never local.
Key: key.AsRawKey(),
},
MaxRanges: ds.rangeLookupMaxRanges,
ConsiderIntents: considerIntents,
Reverse: useReverseScan,
})
replicas := newReplicaSlice(ds.gossip, desc)
replicas.Shuffle()
// TODO(tschottdorf): Ideally we would use the trace of the request which
// caused this lookup.
_ = context.TODO()
br, err := ds.sendRPC(ds.Ctx, desc.RangeID, replicas, ba)
if err != nil {
return nil, nil, roachpb.NewError(err)
}
if br.Error != nil {
return nil, nil, br.Error
}
resp := br.Responses[0].GetInner().(*roachpb.RangeLookupResponse)
return resp.Ranges, resp.PrefetchedRanges, nil
}
// send runs the specified calls synchronously in a single batch and returns
// any errors. Returns a nil response for empty input (no requests).
func (db *DB) send(maxScanResults int64, readConsistency roachpb.ReadConsistencyType,
reqs ...roachpb.Request) (*roachpb.BatchResponse, *roachpb.Error) {
if len(reqs) == 0 {
return nil, nil
}
if readConsistency == roachpb.INCONSISTENT {
for _, req := range reqs {
if req.Method() != roachpb.Get && req.Method() != roachpb.Scan &&
req.Method() != roachpb.ReverseScan {
return nil, roachpb.NewErrorf("method %s not allowed with INCONSISTENT batch", req.Method)
}
}
}
ba := roachpb.BatchRequest{}
ba.Add(reqs...)
ba.MaxScanResults = maxScanResults
if db.userPriority != 1 {
ba.UserPriority = db.userPriority
}
ba.ReadConsistency = readConsistency
tracing.AnnotateTrace()
br, pErr := db.sender.Send(context.TODO(), ba)
if pErr != nil {
if log.V(1) {
log.Infof("failed batch: %s", pErr)
}
return nil, pErr
}
return br, nil
}
// rangeLookup dispatches an RangeLookup request for the given
// metadata key to the replicas of the given range. Note that we allow
// inconsistent reads when doing range lookups for efficiency. Getting
// stale data is not a correctness problem but instead may
// infrequently result in additional latency as additional range
// lookups may be required. Note also that rangeLookup bypasses the
// DistSender's Send() method, so there is no error inspection and
// retry logic here; this is not an issue since the lookup performs a
// single inconsistent read only.
func (ds *DistSender) rangeLookup(key roachpb.Key, options lookupOptions,
desc *roachpb.RangeDescriptor) ([]roachpb.RangeDescriptor, error) {
ba := roachpb.BatchRequest{}
ba.ReadConsistency = roachpb.INCONSISTENT
ba.Add(&roachpb.RangeLookupRequest{
RequestHeader: roachpb.RequestHeader{
Key: key,
ReadConsistency: roachpb.INCONSISTENT,
},
MaxRanges: ds.rangeLookupMaxRanges,
ConsiderIntents: options.considerIntents,
Reverse: options.useReverseScan,
})
replicas := newReplicaSlice(ds.gossip, desc)
// TODO(tschottdorf) consider a Trace here, potentially that of the request
// that had the cache miss and waits for the result.
br, err := ds.sendRPC(nil /* Trace */, desc.RangeID, replicas, rpc.OrderRandom, ba)
if err != nil {
return nil, err
}
if err := br.GoError(); err != nil {
return nil, err
}
return br.Responses[0].GetInner().(*roachpb.RangeLookupResponse).Ranges, nil
}
// RangeLookup dispatches an RangeLookup request for the given
// metadata key to the replicas of the given range. Note that we allow
// inconsistent reads when doing range lookups for efficiency. Getting
// stale data is not a correctness problem but instead may
// infrequently result in additional latency as additional range
// lookups may be required. Note also that rangeLookup bypasses the
// DistSender's Send() method, so there is no error inspection and
// retry logic here; this is not an issue since the lookup performs a
// single inconsistent read only.
func (ds *DistSender) RangeLookup(key roachpb.RKey, desc *roachpb.RangeDescriptor, considerIntents, useReverseScan bool) ([]roachpb.RangeDescriptor, *roachpb.Error) {
ba := roachpb.BatchRequest{}
ba.ReadConsistency = roachpb.INCONSISTENT
ba.Add(&roachpb.RangeLookupRequest{
Span: roachpb.Span{
// We can interpret the RKey as a Key here since it's a metadata
// lookup; those are never local.
Key: key.AsRawKey(),
},
MaxRanges: ds.rangeLookupMaxRanges,
ConsiderIntents: considerIntents,
Reverse: useReverseScan,
})
replicas := newReplicaSlice(ds.gossip, desc)
trace := ds.Tracer.StartSpan("range lookup")
defer trace.Finish()
// TODO(tschottdorf): Ideally we would use the trace of the request which
// caused this lookup instead of a new one.
br, err := ds.sendRPC(trace, desc.RangeID, replicas, orderRandom, ba)
if err != nil {
return nil, err
}
if br.Error != nil {
return nil, br.Error
}
return br.Responses[0].GetInner().(*roachpb.RangeLookupResponse).Ranges, nil
}
// rangeLookup implements the rangeDescriptorDB interface. It looks up
// the descriptors for the given (meta) key.
func (ls *LocalSender) rangeLookup(key roachpb.Key, options lookupOptions, _ *roachpb.RangeDescriptor) ([]roachpb.RangeDescriptor, error) {
ba := roachpb.BatchRequest{}
ba.ReadConsistency = roachpb.INCONSISTENT
ba.Add(&roachpb.RangeLookupRequest{
RequestHeader: roachpb.RequestHeader{
Key: key,
},
MaxRanges: 1,
ConsiderIntents: options.considerIntents,
Reverse: options.useReverseScan,
})
br, pErr := ls.Send(context.Background(), ba)
if pErr != nil {
return nil, pErr.GoError()
}
return br.Responses[0].GetInner().(*roachpb.RangeLookupResponse).Ranges, nil
}
// RangeLookup implements the RangeDescriptorDB interface. It looks up
// the descriptors for the given (meta) key.
func (ls *Stores) RangeLookup(key roachpb.RKey, _ *roachpb.RangeDescriptor, considerIntents, useReverseScan bool) ([]roachpb.RangeDescriptor, *roachpb.Error) {
ba := roachpb.BatchRequest{}
ba.ReadConsistency = roachpb.INCONSISTENT
ba.Add(&roachpb.RangeLookupRequest{
Span: roachpb.Span{
// key is a meta key, so it's guaranteed not local-prefixed.
Key: key.AsRawKey(),
},
MaxRanges: 1,
ConsiderIntents: considerIntents,
Reverse: useReverseScan,
})
br, pErr := ls.Send(context.Background(), ba)
if pErr != nil {
return nil, pErr
}
return br.Responses[0].GetInner().(*roachpb.RangeLookupResponse).Ranges, nil
}