fix: avoid data race when setting memdb footprint hook

Signed-off-by: ekexium <eke@fastmail.com>
tikv · Nov 23, 2022 · 21fe69b · 21fe69b
1 parent e9db9e6
commit 21fe69b
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/internal/unionstore/memdb.go b/internal/unionstore/memdb.go
@@ -871,8 +871,11 @@ func (db *MemDB) SetMemoryFootprintChangeHook(hook func(uint64)) {
 	innerHook := func() {
 		hook(db.allocator.capacity + db.vlog.capacity)
 	}
-	db.allocator.memChangeHook = innerHook
-	db.vlog.memChangeHook = innerHook
+	if db.allocator.memChangeHook == nil {
+		// always set together
+		db.allocator.memChangeHook = innerHook
+		db.vlog.memChangeHook = innerHook
+	}
 }
 
 // Mem returns the current memory footprint