diff --git a/pgxn/neon/file_cache.c b/pgxn/neon/file_cache.c
index 2da24d53f9..db19475335 100644
--- a/pgxn/neon/file_cache.c
+++ b/pgxn/neon/file_cache.c
@@ -632,6 +632,7 @@ lfc_prewarm(FileCacheStateEntry* fs, size_t n_entries)
 	/* Do not prewarm more entries than LFC limit */
 	if (lfc_ctl->limit <= lfc_ctl->size)
 	{
+		elog(LOG, "LFC: skip prewarm because LFC limit is smaller than prewarm size");
 		LWLockRelease(lfc_lock);
 		return;
 	}
@@ -641,12 +642,19 @@ lfc_prewarm(FileCacheStateEntry* fs, size_t n_entries)
 		n_entries = lfc_ctl->limit - lfc_ctl->size;
 	}
 
-	LWLockRelease(lfc_lock);
-
+	if (lfc_ctl->prewarm_total_chunks != lfc_ctl->prewarm_curr_chunk)
+	{
+		elog(LOG, "LFC: skip prewarm because concurrent prewarm is detected");
+		LWLockRelease(lfc_lock);
+		return;
+	}
 	/* Initialize fields used to track prewarming progress */
 	lfc_ctl->prewarm_total_chunks = n_entries;
 	lfc_ctl->prewarm_curr_chunk = 0;
 
+	LWLockRelease(lfc_lock);
+
+
 	ring = (PrewarmRequest*)palloc(sizeof(PrewarmRequest)*ring_size);
 
 	elog(LOG, "LFC: start loading %ld chunks", (long)n_entries);
diff --git a/pgxn/neon/pagestore_client.h b/pgxn/neon/pagestore_client.h
index 858dd8b85f..8c25958e5b 100644
--- a/pgxn/neon/pagestore_client.h
+++ b/pgxn/neon/pagestore_client.h
@@ -186,6 +186,7 @@ typedef struct
 {
 	/*
 	 * Send this request to the PageServer associated with this shard.
+	 * This function assigns request_id to the request which can be extracted by caller from request struct.
 	 */
 	bool		(*send) (shardno_t  shard_no, NeonRequest * request);
 	/*