From 6df823f8040c376ca96f6cba8879cf878737fa93 Mon Sep 17 00:00:00 2001
From: luoxiaojian <lxj193371@alibaba-inc.com>
Date: Wed, 17 Jun 2026 11:28:36 +0800
Subject: [PATCH] fix(hnsw): restore persisted info on reopen for UniformInt8
 quantizer (#496)

---
 src/core/algorithm/hnsw/hnsw_streamer.cc | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/core/algorithm/hnsw/hnsw_streamer.cc b/src/core/algorithm/hnsw/hnsw_streamer.cc
index 92b2cf7..64ff5a7 100644
--- a/src/core/algorithm/hnsw/hnsw_streamer.cc
+++ b/src/core/algorithm/hnsw/hnsw_streamer.cc
@@ -293,6 +293,18 @@ int HnswStreamer::open(IndexStorage::Pointer stg) {
     auto metric_params = index_meta.metric_params();
     metric_params.merge(meta_.metric_params());
     meta_.set_metric(index_meta.metric_name(), 0, metric_params);
+
+    // Restore converter/reformer from the persisted meta
+    if (!index_meta.reformer_name().empty()) {
+      meta_.set_reformer(index_meta.reformer_name(),
+                         index_meta.reformer_revision(),
+                         index_meta.reformer_params());
+    }
+    if (!index_meta.converter_name().empty()) {
+      meta_.set_converter(index_meta.converter_name(),
+                          index_meta.converter_revision(),
+                          index_meta.converter_params());
+    }
   }
 
   metric_ = IndexFactory::CreateMetric(meta_.metric_name());