diff --git a/eden/scm/lib/checkout/src/lib.rs b/eden/scm/lib/checkout/src/lib.rs
index 1dc2134a5e..a8cac5083c 100644
--- a/eden/scm/lib/checkout/src/lib.rs
+++ b/eden/scm/lib/checkout/src/lib.rs
@@ -6,7 +6,7 @@
  */
 
 use anyhow::{bail, format_err, Result};
-use futures::{stream, try_join, Stream, StreamExt};
+use futures::{stream, try_join, Stream, StreamExt, TryStreamExt};
 use manifest::{DiffEntry, DiffType, FileMetadata, FileType};
 use revisionstore::{HgIdDataStore, RemoteDataStore, StoreKey, StoreResult};
 use std::fmt;
@@ -15,6 +15,8 @@ use std::sync::Arc;
 use types::{HgId, Key, RepoPathBuf};
 use vfs::{UpdateFlag, VFS};
 
+const PREFETCH_CHUNK_SIZE: usize = 1000;
+
 /// Contains lists of files to be removed / updated during checkout.
 pub struct CheckoutPlan {
     /// Files to be removed.
@@ -110,7 +112,7 @@ impl CheckoutPlan {
     /// Pending storage futures are dropped when error is returned
     pub async fn apply_stream<
         S: Stream<Item = Result<StoreResult<Vec<u8>>>> + Unpin,
-        F: FnOnce(Vec<Key>) -> Result<S>,
+        F: FnOnce(Vec<Key>) -> S,
     >(
         self,
         vfs: &VFS,
@@ -132,7 +134,7 @@ impl CheckoutPlan {
             .map(|u| Key::new(u.path.clone(), u.content_hgid))
             .collect();
 
-        let data_stream = f(keys)?;
+        let data_stream = f(keys);
 
         let update_content = data_stream
             .zip(stream::iter(self.update_content.into_iter()))
@@ -171,9 +173,7 @@ impl CheckoutPlan {
         store: &DS,
     ) -> Result<CheckoutStats> {
         self.apply_stream(vfs, |keys| {
-            Ok(stream::iter(
-                keys.into_iter().map(|key| store.get(StoreKey::HgId(key))),
-            ))
+            stream::iter(keys.into_iter().map(|key| store.get(StoreKey::HgId(key))))
         })
         .await
     }
@@ -184,11 +184,13 @@ impl CheckoutPlan {
         store: &DS,
     ) -> Result<CheckoutStats> {
         self.apply_stream(vfs, |keys| {
-            let store_keys: Vec<_> = keys.into_iter().map(StoreKey::HgId).collect();
-            store.prefetch(&store_keys)?;
-            Ok(stream::iter(
-                store_keys.into_iter().map(|key| store.get(key)),
-            ))
+            stream::iter(keys.into_iter().map(StoreKey::HgId))
+                .chunks(PREFETCH_CHUNK_SIZE)
+                .map(|chunk| -> Result<_> {
+                    store.prefetch(&chunk)?;
+                    Ok(stream::iter(chunk.into_iter().map(|key| store.get(key))))
+                })
+                .try_flatten()
         })
         .await
     }
@@ -544,8 +546,8 @@ mod test {
         Ok(())
     }
 
-    fn dummy_fs(v: Vec<Key>) -> Result<impl Stream<Item = Result<StoreResult<Vec<u8>>>>> {
-        Ok(stream::iter(v).map(|key| Ok(StoreResult::Found(hgid_file(&key.hgid)))))
+    fn dummy_fs(v: Vec<Key>) -> impl Stream<Item = Result<StoreResult<Vec<u8>>>> {
+        stream::iter(v).map(|key| Ok(StoreResult::Found(hgid_file(&key.hgid))))
     }
 
     fn hgid_file(hgid: &HgId) -> Vec<u8> {