diff --git a/libc/malloc_debug/malloc_debug.cpp b/libc/malloc_debug/malloc_debug.cpp
index 7b0f59995..b06ec9eeb 100644
--- a/libc/malloc_debug/malloc_debug.cpp
+++ b/libc/malloc_debug/malloc_debug.cpp
@@ -496,7 +496,7 @@ void debug_free_malloc_leak_info(uint8_t* info) {
   g_dispatch->free(info);
   // Purge the memory that was freed since a significant amount of
   // memory could have been allocated and freed.
-  g_dispatch->mallopt(M_PURGE, 0);
+  g_dispatch->mallopt(M_PURGE_ALL, 0);
 }
 
 size_t debug_malloc_usable_size(void* pointer) {
@@ -1123,7 +1123,7 @@ static void write_dump(int fd) {
 
   // Purge the memory that was allocated and freed during this operation
   // since it can be large enough to expand the RSS significantly.
-  g_dispatch->mallopt(M_PURGE, 0);
+  g_dispatch->mallopt(M_PURGE_ALL, 0);
 }
 
 bool debug_write_malloc_leak_info(FILE* fp) {