Set the decay timer for all forked apps.
This will cause native memory frees to be less expensive, but it will cost
a bit of PSS that might hang around.
Bug: 36401135
Test: Built and booted bullhead.
Test: Ran jemalloc unit tests.
Test: Ran bionic unit tests.
Test: Ran a test that allocated and free'd a large piece of memory,
Test: and verified that after changing the parameter, the PSS
Test: sticks around (decay timer set to 1), the PSS is purged (decay
Test: timer set to 0).
Change-Id: I140b26986f3f81fddd5b9ed9c9e4f2d4977b819b
diff --git a/core/jni/com_android_internal_os_Zygote.cpp b/core/jni/com_android_internal_os_Zygote.cpp
index 6000fb5..d73e7dd 100644
--- a/core/jni/com_android_internal_os_Zygote.cpp
+++ b/core/jni/com_android_internal_os_Zygote.cpp
@@ -27,6 +27,7 @@
#include <fcntl.h>
#include <grp.h>
#include <inttypes.h>
+#include <malloc.h>
#include <mntent.h>
#include <paths.h>
#include <signal.h>
@@ -519,6 +520,9 @@
// The child process.
gMallocLeakZygoteChild = 1;
+ // Set the jemalloc decay time to 1.
+ mallopt(M_DECAY_TIME, 1);
+
// Clean up any descriptors which must be closed immediately
DetachDescriptors(env, fdsToClose);