From 1da4b88dd5a49ef9821bd476980226b39859e793 Mon Sep 17 00:00:00 2001
From: Yuchen Kou <kouyuchen@approaching.ai>
Date: Tue, 1 Sep 2026 14:27:12 +0800
Subject: [PATCH] [Store] Fix snapshot test eviction race

---
 .../snapshot/master_service_test_for_snapshot_base.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/mooncake-store/tests/ha/snapshot/master_service_test_for_snapshot_base.h b/mooncake-store/tests/ha/snapshot/master_service_test_for_snapshot_base.h
index 48659096c4..d0bd912094 100644
--- a/mooncake-store/tests/ha/snapshot/master_service_test_for_snapshot_base.h
+++ b/mooncake-store/tests/ha/snapshot/master_service_test_for_snapshot_base.h
@@ -19,6 +19,7 @@
 #include <iomanip>
 #include <map>
 #include <memory>
+#include <mutex>
 #include <sstream>
 #include <thread>
 #include <unordered_map>
@@ -165,6 +166,8 @@ class MasterServiceSnapshotTestBase : public ::testing::Test {
     // private members
     static tl::expected<void, SerializationError> CallPersistState(
         MasterService* service, const std::string& snapshot_id) {
+        std::unique_lock<std::shared_mutex> snapshot_lock(
+            service->snapshot_mutex_);
         // If snapshot_manager_ exists, use it; otherwise create a temporary one
         if (service->snapshot_manager_) {
             return service->snapshot_manager_->PersistState(snapshot_id);
@@ -827,6 +830,15 @@ class MasterServiceSnapshotTestBase : public ::testing::Test {
             << "Use 'service_.reset(new MasterService(...))' instead of "
                "'std::unique_ptr<MasterService> service_(...)'";
 
+        // Freeze the original service before snapshot/restore validation. The
+        // eviction worker can otherwise mutate replica metadata while the
+        // snapshot is being serialized, making the post-restore comparison
+        // compare two different points in time.
+        service_->eviction_running_ = false;
+        if (service_->eviction_thread_.joinable()) {
+            service_->eviction_thread_.join();
+        }
+
         // Some test configs may not enable snapshot/restore, so the backend
         // is not created in the constructor. We create it here for TearDown
         // validation.