PackageDexOptimizer 逻辑

计划中的 PackageDexOptimizer 是旧架构名称。Android 17 的 PMS 源码中，安装 dexopt 的执行入口已经是 DexOptHelper，实际编译由 ART Service 的 ArtManagerLocal 完成；PMS 不再自己组装 dex2oat 命令，也没有一个可直接调用的 PackageDexOptimizer 类。

1. 架构迁移

历史职责	Android 17 owner
选择安装编译 reason	`DexOptHelper` / `InstallScenarioHelper`
组装 dexopt 参数	`DexOptHelper.getDexoptParamsByInstallRequest`
遍历 dex 容器并编译	ART Service
生成 oat/vdex/art	ART Service / artd
返回每文件结果	`DexoptResult`
安装请求记录状态	`InstallRequest.onDexoptFinished`

2. 安装入口

源码文件：frameworks/base/services/core/java/com/android/server/pm/InstallPackageHelper.java

java

CompletableFuture<Void> dexoptFuture =
        mPm.getDexOptHelper()
                .performDexoptIfNeededAsync(request);

安装包扫描完成后，InstallPackageHelper 把 InstallRequest 交给 DexOptHelper。返回 Future 是安装流程的同步点：是否等待它由调用方的安装编排决定，但 dexopt 本身在专用 executor 中执行。

3. 参数组装

源码文件：frameworks/base/services/core/java/com/android/server/pm/DexOptHelper.java

java

private DexoptParams getDexoptParamsByInstallRequest(
        InstallRequest installRequest) {
    String compilationReason = mInstallScenarioHelper
            .getCompilationReasonForInstallScenario(
                    installRequest.getInstallScenario());
    var builder = new DexoptParams.Builder(compilationReason);
    if (installRequest.getInstallReason()
            == INSTALL_REASON_DEVICE_RESTORE
            || installRequest.getInstallReason()
            == INSTALL_REASON_DEVICE_SETUP) {
        builder.setPriorityClass(
                ArtFlags.PRIORITY_INTERACTIVE_FAST);
    }
    if (installRequest.getDexoptCompilerFilter() != null) {
        builder.setCompilerFilter(
                installRequest.getDexoptCompilerFilter());
    } else if (shouldSkipDexopt(installRequest)) {
        builder.setCompilerFilter(
                DexoptParams.COMPILER_FILTER_NOOP);
    }
    if ((installRequest.getInstallFlags()
            & PackageManager.INSTALL_IGNORE_DEXOPT_PROFILE) != 0) {
        builder.setFlags(
                ArtFlags.FLAG_IGNORE_PROFILE,
                ArtFlags.FLAG_IGNORE_PROFILE);
    }
    return builder.build();
}

PMS 只组装 reason、priority、compiler filter 和 profile flag。真正的 filter 调整、dex 文件遍历、ABI 选择和产物写入属于 ART Service。

4. 安装场景 reason

源码文件：frameworks/base/services/core/java/com/android/server/pm/InstallScenarioHelper.java

java

public String getCompilationReasonForInstallScenario(
        int installScenario) {
    switch (installScenario) {
        case PackageManager.INSTALL_SCENARIO_DEFAULT:
            return ReasonMapping.REASON_INSTALL;
        case PackageManager.INSTALL_SCENARIO_FAST:
            return ReasonMapping.REASON_INSTALL_FAST;
        case PackageManager.INSTALL_SCENARIO_BULK:
            return shouldDowngradeBulkInstall()
                    ? ReasonMapping.REASON_INSTALL_BULK_DOWNGRADED
                    : ReasonMapping.REASON_INSTALL_BULK;
        case PackageManager.INSTALL_SCENARIO_BULK_SECONDARY:
            return shouldDowngradeBulkInstall()
                    ? ReasonMapping.REASON_INSTALL_BULK_SECONDARY_DOWNGRADED
                    : ReasonMapping.REASON_INSTALL_BULK_SECONDARY;
        default:
            return ReasonMapping.REASON_INSTALL;
    }
}

reason 不是日志文本，而是 ART Service 的策略输入。bulk 场景还会根据电量/热状态选择 downgraded reason，影响 ART 后续编译强度。

5. ART 调用条件

java

private static boolean shouldCallArtService(
        InstallRequest installRequest) {
    final boolean isApex =
            (installRequest.getScanFlags() & SCAN_AS_APEX) != 0;
    final boolean instantApp =
            (installRequest.getScanFlags()
                    & SCAN_AS_INSTANT_APP) != 0;
    final PackageSetting ps =
            installRequest.getScannedPackageSetting();
    final AndroidPackage pkg = ps.getPkg();
    final boolean performDexOptForRollback =
            !(installRequest.isRollback()
            && installRequest.getInstallSource()
                    .mInitiatingPackageName.equals("android"));
    return !instantApp && pkg != null
            && !isApex && performDexOptForRollback;
}

APEX、Instant App、没有已扫描 AndroidPackage、system 发起 rollback 不调用 ART Service。这个判断发生在异步任务提交前，返回 completed Future。

6. NOOP 边界

java

private static boolean shouldSkipDexopt(
        InstallRequest installRequest) {
    PackageSetting ps =
            installRequest.getScannedPackageSetting();
    AndroidPackage pkg = ps.getPkg();
    boolean onIncremental =
            isIncrementalPath(ps.getPathString());
    return pkg == null || pkg.isDebuggable() || onIncremental;
}

debuggable 或 Incremental FS 只触发 NOOP compiler filter，不等于完全跳过 ART Service。这样 ART 仍能接收统一请求、记录结果，并由自身决定是否有可执行的优化动作。

7. Snapshot 交接

源码文件：frameworks/base/services/core/java/com/android/server/pm/DexOptHelper.java

java

private DexoptResult dexoptPackageUsingArtService(
        InstallRequest installRequest) {
    final PackageSetting ps =
            installRequest.getScannedPackageSetting();
    PackageManagerLocal packageManagerLocal =
            LocalManagerRegistry.getManager(
                    PackageManagerLocal.class);
    try (PackageManagerLocal.FilteredSnapshot snapshot =
            PackageManagerLocalImpl.withFilteredSnapshot(
                    packageManagerLocal, ps)) {
        DexoptParams params =
                getDexoptParamsByInstallRequest(installRequest);
        return getArtManagerLocal().dexoptPackage(
                snapshot, ps.getPackageName(), params);
    }
}

PMS 以目标 PackageSetting 创建 filtered snapshot，再把包名和参数交给 ART。快照是跨模块契约：ART 可以读取编译所需包、代码路径和依赖，但不应直接访问 PMS 的可变全局状态。

8. 异步失败语义

java

CompletableFuture.runAsync(() -> {
    try {
        Trace.traceBegin(
                TRACE_TAG_PACKAGE_MANAGER, "dexopt");
        DexoptResult result =
                dexoptPackageUsingArtService(installRequest);
        installRequest.onDexoptFinished(result);
    } finally {
        Trace.traceEnd(
                TRACE_TAG_PACKAGE_MANAGER);
    }
}, sDexoptExecutor).exceptionally(t -> {
    Slog.wtf(TAG,
            "Dexopt encountered a fatal error", t);
    return null;
});

正常编译失败应作为 DexoptResult.DEXOPT_FAILED 返回；只有未预期异常才进入 exceptionally。普通 APK 安装不因 dexopt 失败而失败，运行时可以解释执行，后续后台 dexopt 再尝试。

9. 结果结构

源码文件：frameworks/base/services/core/java/com/android/server/pm/InstallRequest.java

java

public void onDexoptFinished(
        DexoptResult dexoptResult) {
    for (PackageDexoptResult packageResult :
            dexoptResult.getPackageDexoptResults()) {
        for (DexContainerFileDexoptResult fileResult :
                packageResult.getDexContainerFileDexoptResults()) {
            if (fileResult.getStatus()
                    == DexoptResult.DEXOPT_FAILED) {
                addWarning(
                        "Error occurred during dexopt when "
                                + "processing external profiles");
            }
        }
    }
    mDexoptStatus = dexoptResult.getFinalStatus();
}

InstallRequest 记录最终状态和 warning；它不重新执行编译，也不把单个 dex 容器失败改写为安装失败。调试时应继续查看每个 dex container 的实际 filter 和 status。

10. dump 与人工验证

源码文件：frameworks/base/services/core/java/com/android/server/pm/DexOptHelper.java

java

public static void dumpDexoptState(
        @NonNull IndentingPrintWriter ipw,
        @NonNull PackageDataSnapshot computer,
        @Nullable String packageName) {
    try (PackageManagerLocal.FilteredSnapshot snapshot =
            getPackageManagerLocal()
                    .withUnownedFilteredSnapshot(computer)) {
        if (packageName != null) {
            getArtManagerLocal().dumpPackage(
                    ipw, snapshot, packageName);
        } else {
            getArtManagerLocal().dump(ipw, snapshot);
        }
    }
}

dumpsys package 的 dexopt 状态由 ART manager 输出。单包 dump 遇到并发删除可能抛 IllegalArgumentException；这反映的是快照与当前包集合的竞态，不代表编译器一定失败。

11. 排查清单

先确认安装请求是否真正进入 performDexoptIfNeededAsync。
shouldCallArtService=false 时检查 APEX、Instant App、pkg 为空和 system rollback。
ART 被调用但无产物时检查 NOOP、Incremental FS、compiler filter 和 ART Service 状态。
查看 DexoptResult 的 package/dex container 明细，不只看安装结果码。
检查 filtered snapshot 是否包含目标包和代码路径。
用 dumpDexoptState 对照实际 reason、filter、status 和 artifacts。

12. 源码阅读路线

InstallPackageHelper：确认安装流程何时提交 dexopt。
DexOptHelper.getDexoptParamsByInstallRequest：参数来源和优先级。
shouldCallArtService/shouldSkipDexopt：调用与 NOOP 边界。
dexoptPackageUsingArtService：filtered snapshot 和 ART 交接。
InstallRequest.onDexoptFinished：状态、warning 和安装继续语义。
ART Service 的 ArtManagerLocal.dexoptPackage：继续阅读实际编译执行。

Android 17 的 PackageDexOptimizer 职责已经拆分：PMS 负责调度和上下文，ART Service 负责优化决策与执行，InstallRequest 负责接收结果。理解这个边界，比继续寻找一个不存在的 PMS 内部 PackageDexOptimizer 类更接近当前源码。

PackageDexOptimizer 逻辑 ​

1. 架构迁移 ​

2. 安装入口 ​

3. 参数组装 ​

4. 安装场景 reason ​

5. ART 调用条件 ​

6. NOOP 边界 ​

7. Snapshot 交接 ​

8. 异步失败语义 ​

9. 结果结构 ​

10. dump 与人工验证 ​

11. 排查清单 ​

12. 源码阅读路线 ​

PackageDexOptimizer 逻辑

1. 架构迁移

2. 安装入口

3. 参数组装

4. 安装场景 reason

5. ART 调用条件

6. NOOP 边界

7. Snapshot 交接

8. 异步失败语义

9. 结果结构

10. dump 与人工验证

11. 排查清单

12. 源码阅读路线