diff --git a/include/jemalloc/internal/arena.h b/include/jemalloc/internal/arena.h
index 1ab91ea..df6e0b2 100644
--- a/include/jemalloc/internal/arena.h
+++ b/include/jemalloc/internal/arena.h
@@ -30,13 +30,16 @@
 	purge_mode_limit = 2
 } purge_mode_t;
 /* ANDROID change */
-/* Use the decay mode purge method. Do not set this value to zero, since
- * forcing a purge immediately affects performance negatively. Using a
- * small value provides a compromise between performance and extra PSS.
+/* Use the decay mode purge method.
+ * Setting this value to zero results in performance issues because it
+ * causes purges at every free. Leave the default at zero, but zygote
+ * processes will set this to one using mallopt. This allows apps which
+ * tend to be active to benefit from the extra performance, but allow system
+ * servers to free PSS while they are sitting idle.
  */
 #define	PURGE_DEFAULT		purge_mode_decay
 /* Default decay time in seconds. */
-#define	DECAY_TIME_DEFAULT	1
+#define	DECAY_TIME_DEFAULT	0
 /* End ANDROID change */
 /* Number of event ticks between time checks. */
 #define	DECAY_NTICKS_PER_UPDATE	1000