一、 提高APP 安装速度方案
提高app安装速度，主要是从dex2oat着手，主要涉及修改点为PackageManagerservice.java的 executePostCommitSteps方法。
Facebook 、微信安装速度的参考解决方案如下：
修改类如下：
frameworks/base/services/core/java/com/android/server/pm/PackageManagerService.java
@@ -17209,7 +17209,12 @@ public class PackageManagerService extends PackageManagerServiceExAbs
// method because `pkg` may not be in `mPackages` yet.
//
// Also, don't fail application installs if the dexopt step fails.
- DexoptOptions dexoptOptions = new DexoptOptions(packageName,
+ DexoptOptions dexoptOptions;
+ if("com.tencent.mm".equals(pkg.packageName)||"com.facebook.katana".equals(pkg.packageName)){
+ dexoptOptions = new DexoptOptions(pkg.packageName,REASON_INSTALL, "verify", null,
+ DexoptOptions.DEXOPT_BOOT_COMPLETE |DexoptOptions.DEXOPT_INSTALL_WITH_DEX_METADATA_FILE);
+ }else{
+ dexoptOptions = new DexoptOptions(packageName,
REASON_INSTALL,
DexoptOptions.DEXOPT_BOOT_COMPLETE
| DexoptOptions.DEXOPT_INSTALL_WITH_DEX_METADATA_FILE);
@@ -17218,6 +17223,7 @@ public class PackageManagerService extends PackageManagerServiceExAbs
getOrCreateCompilerPackageStats(pkg),
mDexManager.getPackageUseInfoOrDefault(packageName),
dexoptOptions);
+ }
Trace.traceEnd(TRACE_TAG_PACKAGE_MANAGER);
}
--
2.17.1
二、MTK 平台参考方案
Android O版本、AndroidN版本
1.ROM过大可以通过调整--compiler-filter，减少apk生成odex文件所占据空间的大小，通常来说odex+vdex文件越大，说明dex2oat优化的类越多越彻底，性能也相对较好；
2.Apk安装时间过长可以通过调整--compiler-filter，加快安装；
修改dex2oat的--compiler-filter选项；
oat_location_为要修改apk的关键字，通常使用包名，比如微信：com.tencent.mm；
/art/dex2oat/dex2oat.cc
void ParseArgs(int argc, char** argv) {
original_argc = argc;
original_argv = argv;
InitLogging(argv, Runtime::Abort);
// Skip over argv[0].
argv++;
argc--;
if (argc == 0) {
Usage("No arguments specified");
}
……
} else if (option.starts_with("--dirty-image-objects=")) {
dirty_image_objects_filename_ = option.substr(strlen("--dirty-image-objects=")).data();
} else if (!compiler_options_->ParseCompilerOption(option, Usage)) {
Usage("Unknown argument %s", option.data());
}
}
/** MTK begin */
if(oat_location_ != "" && (oat_location_.find("mtk14456") != std::string::npos || oat_location_.find("com.tencent.mm")!= std::string::npos)){
LOG(INFO) << "MTK oat_location_=" << oat_location_ << ",SetCompilerFilter=CompilerOptions::kQuicken";
compiler_options_->SetCompilerFilter(CompilerFilter::kQuicken);
}
/** MTK end */
ProcessOptions(parser_options.get());
// Insert some compiler things.
InsertCompileOptions(argc, argv);
}
下面以Android O版本，微信6.6.2为例：
步骤：
1.下载weixin.apk，重命名为weixin.zip；解压缩，把所有的dex文件push到sdcard
2.adb shell，然后执行下面的命令：
./system/bin/dex2oat --oat-file=/sdcard/mtk14456tools_everything.odex --dex-file=/sdcard/classes.dex --dex-file=/sdcard/classes2.dex --dex-file=/sdcard/classes3.dex --dex-file=/sdcard/classes4.dex --dex-file=/sdcard/classes5.dex --compiler-filter=everything
--compiler-filter参数如下：
--compiler-filter=(assume-verified|extract|verify|quicken|space-profile|space|speed-profile|speed|everything-profile|everything)
通过上面可以得出下面数据：
Time为安装apk时dex2oat的时间；
Odex表示生成odex文件的大小；
Vdex表示生成vdex文件的大小；
表格统计数据是根据下面log和生成在sdcard的odex和vdex得出：
01-01 00:33:58.596 4332-4332/? I/dex2oat: StrippedCommandLine:./system/bin/dex2oat --oat-file=/sdcard/mtk14456tools_everything.odex --dex-file=/sdcard/classes.dex --dex-file=/sdcard/classes2.dex --dex-file=/sdcard/classes3.dex --dex-file=/sdcard/classes4.dex --dex-file=/sdcard/classes5.dex --compiler-filter=everything
01-01 00:34:51.958 4332-4332/? I/dex2oat: dex2oat took 53.364s (341.743s cpu) (threads: 8) arena alloc=27MB (28629200B) java alloc=24MB (25341840B) native alloc=128MB (135004032B) free=29MB (31195264B)