diff --git a/markets/dagstore/wrapper.go b/markets/dagstore/wrapper.go
index 5875aa275..620c97abe 100644
--- a/markets/dagstore/wrapper.go
+++ b/markets/dagstore/wrapper.go
@@ -90,7 +90,7 @@ func NewDAGStore(cfg config.DAGStoreConfig, mountApi MinerAPI) (*dagstore.DAGSto
 		mountApi:   mountApi,
 		failureCh:  failureCh,
 		traceCh:    traceCh,
-		gcInterval: cfg.GCInterval,
+		gcInterval: time.Duration(cfg.GCIntervalMillis) * time.Millisecond,
 	}
 
 	return dagst, w, nil
diff --git a/markets/dagstore/wrapper_test.go b/markets/dagstore/wrapper_test.go
index 1278253f0..c6e4e2f38 100644
--- a/markets/dagstore/wrapper_test.go
+++ b/markets/dagstore/wrapper_test.go
@@ -8,9 +8,10 @@ import (
 	"testing"
 	"time"
 
-	"github.com/filecoin-project/lotus/node/config"
 	"golang.org/x/xerrors"
 
+	"github.com/filecoin-project/lotus/node/config"
+
 	"github.com/filecoin-project/dagstore"
 	"github.com/filecoin-project/dagstore/mount"
 	"github.com/filecoin-project/dagstore/shard"
@@ -28,10 +29,10 @@ func TestWrapperAcquireRecovery(t *testing.T) {
 
 	// Create a DAG store wrapper
 	dagst, w, err := NewDAGStore(config.DAGStoreConfig{
-		TransientsDir: t.TempDir(),
-		IndexDir:      t.TempDir(),
-		DatastoreDir:  t.TempDir(),
-		GCInterval:    time.Millisecond,
+		TransientsDir:    t.TempDir(),
+		IndexDir:         t.TempDir(),
+		DatastoreDir:     t.TempDir(),
+		GCIntervalMillis: 1,
 	}, mockLotusMount{})
 	require.NoError(t, err)
 
@@ -81,10 +82,10 @@ func TestWrapperBackground(t *testing.T) {
 
 	// Create a DAG store wrapper
 	dagst, w, err := NewDAGStore(config.DAGStoreConfig{
-		TransientsDir: t.TempDir(),
-		IndexDir:      t.TempDir(),
-		DatastoreDir:  t.TempDir(),
-		GCInterval:    time.Millisecond,
+		TransientsDir:    t.TempDir(),
+		IndexDir:         t.TempDir(),
+		DatastoreDir:     t.TempDir(),
+		GCIntervalMillis: 1,
 	}, mockLotusMount{})
 	require.NoError(t, err)
 
diff --git a/node/config/def.go b/node/config/def.go
index 06e48c731..9b76a2226 100644
--- a/node/config/def.go
+++ b/node/config/def.go
@@ -195,7 +195,7 @@ func DefaultStorageMiner() *StorageMiner {
 			MaxConcurrentIndex:         5,
 			MaxConcurrentReadyFetches:  2,
 			MaxConcurrencyStorageCalls: 100,
-			GCInterval:                 time.Minute,
+			GCIntervalMillis:           60000,
 		},
 	}
 	cfg.Common.API.ListenAddress = "/ip4/127.0.0.1/tcp/2345/http"
diff --git a/node/config/types.go b/node/config/types.go
index ddcb27031..b3f038df4 100644
--- a/node/config/types.go
+++ b/node/config/types.go
@@ -1,11 +1,10 @@
 package config
 
 import (
-	"time"
+	"github.com/ipfs/go-cid"
 
 	"github.com/filecoin-project/lotus/chain/types"
 	sectorstorage "github.com/filecoin-project/lotus/extern/sector-storage"
-	"github.com/ipfs/go-cid"
 )
 
 // // NOTE: ONLY PUT STRUCT DEFINITIONS IN THIS FILE
@@ -55,13 +54,41 @@ type StorageMiner struct {
 }
 
 type DAGStoreConfig struct {
-	TransientsDir              string
-	IndexDir                   string
-	DatastoreDir               string
-	MaxConcurrentIndex         int
-	MaxConcurrentReadyFetches  int
+	// Path to the transients directory. The transients directory caches
+	// unsealed deals that have been fetched from the storage subsystem for
+	// serving retrievals. When empty or omitted, the default value applies.
+	// Default value: $LOTUS_MARKETS_PATH/dagStore/transients (split deployment)
+	// or $LOTUS_MINER_PATH/dagStore/transients (monolith deployment)
+	TransientsDir string
+
+	// Path to indices directory. When empty or omitted, the default value applies.
+	// Default value: $LOTUS_MARKETS_PATH/dagStore/index (split deployment)
+	// or $LOTUS_MINER_PATH/dagStore/index (monolith deployment)
+	IndexDir string
+
+	// Path to datastore directory. The datastore is a KV store tracking the
+	// state of shards known to the DAG store.
+	// Default value: $LOTUS_MARKETS_PATH/dagStore/datastore (split deployment)
+	// or $LOTUS_MINER_PATH/dagStore/datastore (monolith deployment)
+	DatastoreDir string
+
+	// The maximum amount of indexing jobs that can run simultaneously.
+	// Default value: 5.
+	MaxConcurrentIndex int
+
+	// The maximum amount of unsealed deals that can be fetched simultaneously
+	// from the storage subsystem.
+	// Default value: 2.
+	MaxConcurrentReadyFetches int
+
+	// The maximum number of simultaneous inflight API calls to the storage
+	// subsystem.
+	// Default value: 100.
 	MaxConcurrencyStorageCalls int
-	GCInterval                 time.Duration
+
+	// The number of milliseconds between calls to periodic dagstore GC.
+	// Default value: 60000 (60 seconds = 1 minute).
+	GCIntervalMillis int
 }
 
 type MinerSubsystemConfig struct {
diff --git a/node/modules/storageminer_dagstore.go b/node/modules/storageminer_dagstore.go
index 88b9db0e8..6f032ed34 100644
--- a/node/modules/storageminer_dagstore.go
+++ b/node/modules/storageminer_dagstore.go
@@ -9,12 +9,13 @@ import (
 
 	"github.com/filecoin-project/dagstore"
 	"github.com/filecoin-project/go-fil-markets/retrievalmarket"
+	"go.uber.org/fx"
+	"golang.org/x/xerrors"
+
 	mdagstore "github.com/filecoin-project/lotus/markets/dagstore"
 	"github.com/filecoin-project/lotus/node/config"
 	"github.com/filecoin-project/lotus/node/modules/dtypes"
 	"github.com/filecoin-project/lotus/node/repo"
-	"go.uber.org/fx"
-	"golang.org/x/xerrors"
 )
 
 const (
@@ -109,7 +110,7 @@ func extractDAGStoreConfig(r repo.LockedRepo) (config.DAGStoreConfig, error) {
 	if err != nil {
 		return config.DAGStoreConfig{}, xerrors.Errorf("could not load config: %w", err)
 	}
-	mcfg, ok := cfg.(config.StorageMiner)
+	mcfg, ok := cfg.(*config.StorageMiner)
 	if !ok {
 		return config.DAGStoreConfig{}, xerrors.Errorf("config not expected type; expected config.StorageMiner, got: %T", cfg)
 	}