Compact system processes. (31faf3f1) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/am/ActivityManagerService.java

+5 −0

Original line number	Diff line number	Diff line
		@@ -5121,6 +5121,7 @@ public class ActivityManagerService extends IActivityManager.Stub
		String data, Bundle extras, boolean ordered,
		boolean sticky, int sendingUser) {
		synchronized (ActivityManagerService.this) {
		mOomAdjuster.mAppCompact.compactAllSystem();
		requestPssAllProcsLocked(SystemClock.uptimeMillis(), true, false);
		}
		}
		@@ -8614,6 +8615,10 @@ public class ActivityManagerService extends IActivityManager.Stub
		synchronized (this) {
		final long now = SystemClock.uptimeMillis();
		final long timeSinceLastIdle = now - mLastIdleTime;

		// Compact all non-zygote processes to freshen up the page cache.
		mOomAdjuster.mAppCompact.compactAllSystem();

		final long lowRamSinceLastIdle = getLowRamTimeSinceIdle(now);
		mLastIdleTime = now;
		mLowRamTimeSinceLastIdle = 0;

services/core/java/com/android/server/am/AppCompactor.java

+18 −0

Original line number	Diff line number	Diff line
		@@ -92,6 +92,7 @@ public final class AppCompactor {
		static final int COMPACT_PROCESS_PERSISTENT = 3;
		static final int COMPACT_PROCESS_BFGS = 4;
		static final int COMPACT_PROCESS_MSG = 1;
		static final int COMPACT_SYSTEM_MSG = 2;

		/**
		* This thread must be moved to the system background cpuset.
		@@ -264,6 +265,16 @@ public final class AppCompactor {
		\|\| (now - app.lastCompactTime) > mCompactThrottleBFGS);
		}

		@GuardedBy("mAm")
		void compactAllSystem() {
		if (mUseCompaction) {
		mCompactionHandler.sendMessage(mCompactionHandler.obtainMessage(
		COMPACT_SYSTEM_MSG));
		}
		}

		private native void compactSystem();

		/**
		* Reads the flag value from DeviceConfig to determine whether app compaction
		* should be enabled, and starts/stops the compaction thread as needed.
		@@ -497,6 +508,13 @@ public final class AppCompactor {
		// nothing to do, presumably the process died
		Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
		}
		break;
		}
		case COMPACT_SYSTEM_MSG: {
		Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "compactSystem");
		compactSystem();
		Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
		break;
		}
		}
		}

services/core/jni/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -50,6 +50,7 @@ cc_library_static {
		"com_android_server_VibratorService.cpp",
		"com_android_server_PersistentDataBlockService.cpp",
		"com_android_server_GraphicsStatsService.cpp",
		"com_android_server_am_AppCompactor.cpp",
		"onload.cpp",
		],

services/core/jni/com_android_server_am_AppCompactor.cpp

0 → 100644

+88 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2019 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		#define LOG_TAG "AppCompactor"
		//#define LOG_NDEBUG 0

		#include <dirent.h>
		#include <stddef.h>
		#include <stdio.h>
		#include <sys/stat.h>
		#include <sys/types.h>
		#include <unistd.h>

		#include <android-base/stringprintf.h>
		#include <android-base/file.h>

		#include <nativehelper/JNIHelp.h>
		#include <android_runtime/AndroidRuntime.h>
		#include <jni.h>

		using android::base::StringPrintf;
		using android::base::WriteStringToFile;

		namespace android {

		// This performs per-process reclaim on all processes belonging to non-app UIDs.
		// For the most part, these are non-zygote processes like Treble HALs, but it
		// also includes zygote-derived processes that run in system UIDs, like bluetooth
		// or potentially some mainline modules. The only process that should definitely
		// not be compacted is system_server, since compacting system_server around the
		// time of BOOT_COMPLETE could result in perceptible issues.
		static void com_android_server_am_AppCompactor_compactSystem(JNIEnv *, jobject) {
		std::unique_ptr<DIR, decltype(&closedir)> proc(opendir("/proc"), closedir);
		struct dirent* current;
		while ((current = readdir(proc.get()))) {
		if (current->d_type != DT_DIR) {
		continue;
		}

		// don't compact system_server, rely on persistent compaction during screen off
		// in order to avoid mmap_sem-related stalls
		if (atoi(current->d_name) == getpid()) {
		continue;
		}

		std::string status_name = StringPrintf("/proc/%s/status", current->d_name);
		struct stat status_info;

		if (stat(status_name.c_str(), &status_info) != 0) {
		// must be some other directory that isn't a pid
		continue;
		}

		// android.os.Process.FIRST_APPLICATION_UID
		if (status_info.st_uid >= 10000) {
		continue;
		}

		std::string reclaim_path = StringPrintf("/proc/%s/reclaim", current->d_name);
		WriteStringToFile(std::string("all"), reclaim_path);
		}
		}

		static const JNINativeMethod sMethods[] = {
		/* name, signature, funcPtr */
		{"compactSystem", "()V", (void*)com_android_server_am_AppCompactor_compactSystem},
		};

		int register_android_server_am_AppCompactor(JNIEnv* env)
		{
		return jniRegisterNativeMethods(env, "com/android/server/am/AppCompactor",
		sMethods, NELEM(sMethods));
		}

		}

services/core/jni/onload.cpp

+2 −0

Original line number	Diff line number	Diff line
		@@ -54,6 +54,7 @@ int register_android_server_GraphicsStatsService(JNIEnv* env);
		int register_android_hardware_display_DisplayViewport(JNIEnv* env);
		int register_android_server_net_NetworkStatsService(JNIEnv* env);
		int register_android_server_security_VerityUtils(JNIEnv* env);
		int register_android_server_am_AppCompactor(JNIEnv* env);
		};

		using namespace android;
		@@ -101,5 +102,6 @@ extern "C" jint JNI_OnLoad(JavaVM* vm, void* /* reserved */)
		register_android_hardware_display_DisplayViewport(env);
		register_android_server_net_NetworkStatsService(env);
		register_android_server_security_VerityUtils(env);
		register_android_server_am_AppCompactor(env);
		return JNI_VERSION_1_4;
		}