diff --git a/extern/sector-storage/stores/remote.go b/extern/sector-storage/stores/remote.go
index bf66c1bb5..dd5add9c8 100644
--- a/extern/sector-storage/stores/remote.go
+++ b/extern/sector-storage/stores/remote.go
@@ -3,6 +3,8 @@ package stores
 import (
 	"context"
 	"encoding/json"
+	"fmt"
+	"io"
 	"io/ioutil"
 	"math/bits"
 	"mime"
@@ -59,6 +61,30 @@ func NewRemote(local *Local, index SectorIndex, auth http.Header, fetchLimit int
 	}
 }
 
+var SealProofIosizes = map[abi.RegisteredSealProof]uint64{
+	abi.RegisteredSealProof_StackedDrg2KiBV1:   32 * 1024,
+	abi.RegisteredSealProof_StackedDrg8MiBV1:   32 * 1024,
+	abi.RegisteredSealProof_StackedDrg512MiBV1: 1024 * 1024,
+	abi.RegisteredSealProof_StackedDrg32GiBV1:  1024 * 1024,
+	abi.RegisteredSealProof_StackedDrg64GiBV1:  1024 * 1024,
+
+	abi.RegisteredSealProof_StackedDrg2KiBV1_1:   32 * 1024,
+	abi.RegisteredSealProof_StackedDrg8MiBV1_1:   32 * 1024,
+	abi.RegisteredSealProof_StackedDrg512MiBV1_1: 1024 * 1024,
+	abi.RegisteredSealProof_StackedDrg32GiBV1_1:  1024 * 1024,
+	abi.RegisteredSealProof_StackedDrg64GiBV1_1:  1024 * 1024,
+}
+
+const MaxIoSize = 64 * 1024 * 1024
+
+func GetIoSizeByProofType(p abi.RegisteredSealProof) (uint64, error) {
+	size, ok := SealProofIosizes[p]
+	if !ok {
+		return 0, xerrors.Errorf("unsupported proof type: %v", p)
+	}
+	return size, nil
+}
+
 func (r *Remote) AcquireSector(ctx context.Context, s storage.SectorRef, existing storiface.SectorFileType, allocate storiface.SectorFileType, pathType storiface.PathType, op storiface.AcquireMode) (storiface.SectorPaths, storiface.SectorPaths, error) {
 	if existing|allocate != existing^allocate {
 		return storiface.SectorPaths{}, storiface.SectorPaths{}, xerrors.New("can't both find and allocate a sector")
@@ -123,6 +149,12 @@ func (r *Remote) AcquireSector(ctx context.Context, s storage.SectorRef, existin
 	}
 	defer releaseStorage()
 
+	var iosize uint64 = 0
+	ssize, err := GetIoSizeByProofType(s.ProofType)
+	if err == nil {
+		iosize = ssize
+	}
+
 	for _, fileType := range storiface.PathTypes {
 		if fileType&existing == 0 {
 			continue
@@ -135,7 +167,7 @@ func (r *Remote) AcquireSector(ctx context.Context, s storage.SectorRef, existin
 		dest := storiface.PathByType(apaths, fileType)
 		storageID := storiface.PathByType(ids, fileType)
 
-		url, err := r.acquireFromRemote(ctx, s.ID, fileType, dest)
+		url, err := r.acquireFromRemote(ctx, s.ID, fileType, dest, iosize)
 		if err != nil {
 			return storiface.SectorPaths{}, storiface.SectorPaths{}, err
 		}
@@ -170,7 +202,7 @@ func tempFetchDest(spath string, create bool) (string, error) {
 	return filepath.Join(tempdir, b), nil
 }
 
-func (r *Remote) acquireFromRemote(ctx context.Context, s abi.SectorID, fileType storiface.SectorFileType, dest string) (string, error) {
+func (r *Remote) acquireFromRemote(ctx context.Context, s abi.SectorID, fileType storiface.SectorFileType, dest string, iosize uint64) (string, error) {
 	si, err := r.index.StorageFindSector(ctx, s, fileType, 0, false)
 	if err != nil {
 		return "", err
@@ -198,7 +230,7 @@ func (r *Remote) acquireFromRemote(ctx context.Context, s abi.SectorID, fileType
 				return "", xerrors.Errorf("removing dest: %w", err)
 			}
 
-			err = r.fetch(ctx, url, tempDest)
+			err = r.fetch(ctx, url, tempDest, iosize)
 			if err != nil {
 				merr = multierror.Append(merr, xerrors.Errorf("fetch error %s (storage %s) -> %s: %w", url, info.ID, tempDest, err))
 				continue
@@ -218,7 +250,7 @@ func (r *Remote) acquireFromRemote(ctx context.Context, s abi.SectorID, fileType
 	return "", xerrors.Errorf("failed to acquire sector %v from remote (tried %v): %w", s, si, merr)
 }
 
-func (r *Remote) fetch(ctx context.Context, url, outname string) error {
+func (r *Remote) fetch(ctx context.Context, url, outname string, iosize uint64) error {
 	log.Infof("Fetch %s -> %s", url, outname)
 
 	if len(r.limit) >= cap(r.limit) {
@@ -276,12 +308,57 @@ func (r *Remote) fetch(ctx context.Context, url, outname string) error {
 	case "application/x-tar":
 		return tarutil.ExtractTar(resp.Body, outname)
 	case "application/octet-stream":
-		return files.WriteTo(files.NewReaderFile(resp.Body), outname)
+		return WriteWithSize(files.NewReaderFile(resp.Body), outname, iosize)
 	default:
 		return xerrors.Errorf("unknown content type: '%s'", mediatype)
 	}
 }
 
+func WriteWithSize(nd files.Node, fpath string, size uint64) error {
+	switch nd := nd.(type) {
+	case *files.Symlink:
+		return os.Symlink(nd.Target, fpath)
+	case files.File:
+		f, err := os.Create(fpath)
+		defer func() {
+			err = f.Close()
+			if err != nil {
+				log.Warnf("failed to close file:%v, err:%v", fpath, err)
+			}
+		}()
+		if err != nil {
+			return err
+		}
+		if size <= 0 || size > MaxIoSize {
+			_, err = io.Copy(f, nd)
+		} else {
+			buf := make([]byte, size)
+			_, err = io.CopyBuffer(f, nd, buf)
+		}
+
+		if err != nil {
+			return err
+		}
+		return nil
+	case files.Directory:
+		err := os.Mkdir(fpath, 0777)
+		if err != nil {
+			return err
+		}
+
+		entries := nd.Entries()
+		for entries.Next() {
+			child := filepath.Join(fpath, entries.Name())
+			if err := WriteWithSize(entries.Node(), child, size); err != nil {
+				return err
+			}
+		}
+		return entries.Err()
+	default:
+		return fmt.Errorf("file type %T at %q is not supported", nd, fpath)
+	}
+}
+
 func (r *Remote) MoveStorage(ctx context.Context, s storage.SectorRef, types storiface.SectorFileType) error {
 	// Make sure we have the data local
 	_, _, err := r.AcquireSector(ctx, s, types, storiface.FTNone, storiface.PathStorage, storiface.AcquireMove)