What will happen if a customer doesn't upload all pieces?

Toyoo · February 20, 2022, 9:26pm

What will happen if a customer only uploads, let say, 35 erasure shares, as opposed to the eighty they’re supposed to do? Will the satellite drop the file, or maybe go for repair after some time?

Just asking out of curiosity.

BrightSilence · February 20, 2022, 10:06pm

The upload will fail with an error that not enough pieces have been uploaded. I think the cleanup for pieces that were uploaded will happen through garbage collection on nodes, but I remember seeing something about metadata on the satellite being cleaned up more quickly to prevent subsequent uploads being blocked because objects already exist. Not sure about the details on that part though.

Toyoo · February 21, 2022, 7:53am

Is this a satellite-side check?

Alexey · February 21, 2022, 8:14am

github.com

storj/storj/blob/0178a13743ed2e2573df689e070330777224fbb9/satellite/nodeselection/uploadselection/state.go#L16

      
        
            import (
            	"context"
            	"sync"
            
            
	"github.com/zeebo/errs"
            
            
	"storj.io/common/storj"
            )
            
            
// ErrNotEnoughNodes is when selecting nodes failed with the given parameters.
            var ErrNotEnoughNodes = errs.Class("not enough nodes")
            
            
// State defines a node selector state that allows for selection.
            type State struct {
            	mu sync.RWMutex
            
            
	stats Stats
            	// netByID returns subnet based on storj.NodeID
            	netByID map[storj.NodeID]string
            	// nonDistinct contains selectors for non-distinct selection.
            	nonDistinct struct {

Toyoo · February 21, 2022, 12:48pm

Are you sure this answers my question? I don’t speak golang, but the comments and function names around suggest to me that this exception is used in case there were not enough available nodes to suggest to the uploading client, and not that the client itself did not upload to the proper number of suggested nodes.

BrightSilence · February 21, 2022, 1:16pm

Yeah, I think it might be more this one.

github.com

storj/uplink/blob/1afcc12de178020d7e99c6b9eb45867baff3fc37/private/ecclient/client.go#L190

      
        
            	mon.IntVal("put_segment_pieces_optimal").Observe(int64(rs.OptimalThreshold()))
            	mon.IntVal("put_segment_pieces_successful").Observe(int64(successfulCount))
            	mon.IntVal("put_segment_pieces_failed").Observe(int64(failureCount))
            	mon.IntVal("put_segment_pieces_canceled").Observe(int64(cancellationCount))
            
            
	if int(successfulCount) <= rs.RepairThreshold() && int(successfulCount) < rs.OptimalThreshold() {
            		return nil, nil, Error.New("successful puts (%d) less than or equal to repair threshold (%d)", successfulCount, rs.RepairThreshold())
            	}
            
            
	if int(successfulCount) < rs.OptimalThreshold() {
            		return nil, nil, Error.New("successful puts (%d) less than success threshold (%d)", successfulCount, rs.OptimalThreshold())
            	}
            
            
	return successfulNodes, successfulHashes, nil
            }
            
            
func (ec *ecClient) PutPiece(ctx, parent context.Context, limit *pb.AddressedOrderLimit, privateKey storj.PiecePrivateKey, data io.ReadCloser) (hash *pb.PieceHash, peerID *identity.PeerIdentity, err error) {
            	nodeName := "nil"
            	if limit != nil {
            		nodeName = limit.GetLimit().StorageNodeId.String()[0:8]
            	}

And the one above.

Toyoo · February 21, 2022, 1:53pm

I see this in the uplink repository. Does this mean this is client-side only?

BrightSilence · February 21, 2022, 3:46pm

I haven’t looked up the code to find what the satellite would do if you submit upload results with insufficient nodes. They may reject it as well and probably should, especially if it’s under the repair threshold. But at the least the official uplink implementations will not even attempt to continue.

BrightSilence · February 21, 2022, 7:43pm

Ok, fine… I couldn’t help myself and looked it up.

It checks each piece’s validity and then…

github.com

storj/storj/blob/ec2bd50bb49ebe718175253dedcf7a00e99479e5/satellite/metainfo/endpoint_segment.go#L208

      
        
            		originalLimits[i] = orderLimit.Limit
            	}
            
            
	// verify the piece upload results
            	validPieces, invalidPieces, err := endpoint.pointerVerification.SelectValidPieces(ctx, req.UploadResult, originalLimits)
            	if err != nil {
            		endpoint.log.Debug("pointer verification failed", zap.Error(err))
            		return nil, rpcstatus.Errorf(rpcstatus.InvalidArgument, "pointer verification failed: %s", err)
            	}
            
            
	if len(validPieces) < int(rs.OptimalShares) {
            		endpoint.log.Debug("Number of valid pieces is less than the success threshold",
            			zap.Int("totalReceivedPieces", len(req.UploadResult)),
            			zap.Int("validPieces", len(validPieces)),
            			zap.Int("invalidPieces", len(invalidPieces)),
            			zap.Int("successThreshold", int(rs.OptimalShares)),
            		)
            
            
		errMsg := fmt.Sprintf("Number of valid pieces (%d) is less than the success threshold (%d). Found %d invalid pieces",
            			len(validPieces),
            			rs.OptimalShares,

So yes, the satellite checks that there are enough pieces and if not doesn’t commit the segment to metadata. (it checks a lot more too, like signatures from nodes etc.)