diff --git a/backends/hostmem.c b/backends/hostmem.c
index 4c05862ed5a89059f1dbca8b9285692a413dfa36..c9ddaec849b459b68c458fd014c90483b8dd405b 100644
--- a/backends/hostmem.c
+++ b/backends/hostmem.c
@@ -273,7 +273,7 @@ static void host_memory_backend_init(Object *obj)
     backend->merge = machine_mem_merge(machine);
     backend->dump = machine_dump_guest_core(machine);
     backend->reserve = true;
-    backend->prealloc_threads = 1;
+    backend->prealloc_threads = machine->smp.cpus;
 }
 
 static void host_memory_backend_post_init(Object *obj)