Add system_server to system group only if per_app_memcg is true
P18 or other high-performance devices shouldn't use per-memcg so
it was disabled on those devices[1]. However, we didn't turn off
for system_server memcg so those devices still have two seperate
LRU groups which would have less efficient memory reclaim.
Therefore, this patch makes memcg use for system_server only if
per_app_memcg is enabled.
[1] https://googleplex-android-review.git.corp.google.com/c/platform/system/core/+/4178592
Bug: 110858093
Test: confirm via cat /dev/memcg/system/tasks is none
Change-Id: Ic0e3157bf8ff5de69767797b5508946ca3efeb68
Merged-In: Ic0e3157bf8ff5de69767797b5508946ca3efeb68
Signed-off-by: Minchan Kim <minchan@google.com>
(cherry picked from commit 5fa8af2b10d24fb6c08099d258bf887baf68ffb0)
diff --git a/core/jni/com_android_internal_os_Zygote.cpp b/core/jni/com_android_internal_os_Zygote.cpp
index 9aa0111..0022cf88 100644
--- a/core/jni/com_android_internal_os_Zygote.cpp
+++ b/core/jni/com_android_internal_os_Zygote.cpp
@@ -46,6 +46,7 @@
#include <unistd.h>
#include "android-base/logging.h"
+#include <android-base/properties.h>
#include <android-base/file.h>
#include <android-base/stringprintf.h>
#include <cutils/fs.h>
@@ -71,6 +72,7 @@
using android::String8;
using android::base::StringPrintf;
using android::base::WriteStringToFile;
+using android::base::GetBoolProperty;
#define CREATE_ERROR(...) StringPrintf("%s:%d: ", __FILE__, __LINE__). \
append(StringPrintf(__VA_ARGS__))
@@ -937,12 +939,16 @@
RuntimeAbort(env, __LINE__, "System server process has died. Restarting Zygote!");
}
- // Assign system_server to the correct memory cgroup.
- // Not all devices mount /dev/memcg so check for the file first
- // to avoid unnecessarily printing errors and denials in the logs.
- if (!access("/dev/memcg/system/tasks", F_OK) &&
+ bool low_ram_device = GetBoolProperty("ro.config.low_ram", false);
+ bool per_app_memcg = GetBoolProperty("ro.config.per_app_memcg", low_ram_device);
+ if (per_app_memcg) {
+ // Assign system_server to the correct memory cgroup.
+ // Not all devices mount /dev/memcg so check for the file first
+ // to avoid unnecessarily printing errors and denials in the logs.
+ if (!access("/dev/memcg/system/tasks", F_OK) &&
!WriteStringToFile(StringPrintf("%d", pid), "/dev/memcg/system/tasks")) {
- ALOGE("couldn't write %d to /dev/memcg/system/tasks", pid);
+ ALOGE("couldn't write %d to /dev/memcg/system/tasks", pid);
+ }
}
}
return pid;