From 727f2207660b7ea5383d3a2122a90cd57ee9b3a9 Mon Sep 17 00:00:00 2001
From: David Anderson <davea@ssl.berkeley.edu>
Date: Sat, 22 Jun 2013 09:35:16 -0700
Subject: [PATCH] client (Android): remove apps from mem when suspending and on
 batteries

If we're on batteries and suspending for any reason other than CPU throttling,
remove apps from memory.
This reduces battery drain in some cases.
---
 client/app_control.cpp | 31 ++++++++++++++++++++-----------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/client/app_control.cpp b/client/app_control.cpp
index bc5c7521e5..f7e02637f4 100644
--- a/client/app_control.cpp
+++ b/client/app_control.cpp
@@ -1048,15 +1048,32 @@ void ACTIVE_TASK_SET::suspend_all(int reason) {
     for (unsigned int i=0; i<active_tasks.size(); i++) {
         ACTIVE_TASK* atp = active_tasks[i];
         if (atp->task_state() != PROCESS_EXECUTING) continue;
-        switch (reason) {
-        case SUSPEND_REASON_CPU_THROTTLE:
+
+        // handle CPU throttling separately
+        //
+        if (reason == SUSPEND_REASON_CPU_THROTTLE) {
             if (atp->result->dont_throttle()) continue;
             // if we're doing CPU throttling,
             // don't suspend CPU apps that use < 1 CPU
             //
             if (!atp->result->uses_coprocs() && atp->app_version->avg_ncpus < 1) continue;
             atp->preempt(REMOVE_NEVER);
-            break;
+            continue;;
+        }
+
+#ifdef ANDROID
+        // On Android, remove apps from memory if on batteries
+        // no matter what the reason for suspension.
+        // The message polling in the BOINC runtime system
+        // imposes an overhead which drains the battery
+        //
+        if (gstate.host_info.host_is_running_on_batteries()) {
+            atp->preempt(REMOVE_ALWAYS);
+            continue;
+        }
+#endif
+
+        switch (reason) {
         case SUSPEND_REASON_BENCHMARKS:
             atp->preempt(REMOVE_NEVER);
             break;
@@ -1076,14 +1093,6 @@ void ACTIVE_TASK_SET::suspend_all(int reason) {
             //
             atp->preempt(REMOVE_NEVER);
             break;
-#ifdef ANDROID
-        case SUSPEND_REASON_BATTERIES:
-            // On Android, remove apps from memory if on batteries.
-            // The message polling in the BOINC runtime system
-            // imposes an overhead which drains the battery a bit
-            atp->preempt(REMOVE_ALWAYS);
-            break;
-#endif
         default:
             atp->preempt(REMOVE_MAYBE_USER);
             break;