native-app-performance

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🇺🇸

Original

English

🇨🇳

Translation

Chinese

Native App Performance (CLI-only)

原生应用性能分析（仅CLI方式）

Goal: record Time Profiler via

xctrace

, extract samples, symbolicate, and propose hotspots without opening Instruments.

目标：通过

xctrace

录制Time Profiler追踪，提取样本、符号化并找出性能热点，无需打开Instruments。

Quick start (CLI)

快速开始（CLI方式）

Record Time Profiler (attach):

bash

undefined

录制Time Profiler（附加进程）：

bash

undefined

Start app yourself, then attach

自行启动应用，然后附加进程

xcrun xctrace record --template 'Time Profiler' --time-limit 90s --output /tmp/App.trace --attach <pid>


2) Record Time Profiler (launch):

```bash
xcrun xctrace record --template 'Time Profiler' --time-limit 90s --output /tmp/App.trace --launch -- /path/App.app/Contents/MacOS/App

Extract time samples:

bash

scripts/extract_time_samples.py --trace /tmp/App.trace --output /tmp/time-sample.xml

Get load address for symbolication:

bash

undefined

xcrun xctrace record --template 'Time Profiler' --time-limit 90s --output /tmp/App.trace --attach <pid>


2) 录制Time Profiler（启动应用）：

```bash
xcrun xctrace record --template 'Time Profiler' --time-limit 90s --output /tmp/App.trace --launch -- /path/App.app/Contents/MacOS/App

提取时间样本：

bash

scripts/extract_time_samples.py --trace /tmp/App.trace --output /tmp/time-sample.xml

获取符号化所需的加载地址：

bash

undefined

While app is running

应用运行时执行

vmmap <pid> | rg -m1 "__TEXT" -n


5) Symbolicate + rank hotspots:

```bash
scripts/top_hotspots.py --samples /tmp/time-sample.xml \
  --binary /path/App.app/Contents/MacOS/App \
  --load-address 0x100000000 --top 30

vmmap <pid> | rg -m1 "__TEXT" -n


5) 符号化并排序性能热点：

```bash
scripts/top_hotspots.py --samples /tmp/time-sample.xml \
  --binary /path/App.app/Contents/MacOS/App \
  --load-address 0x100000000 --top 30

Workflow notes

工作流注意事项

Always confirm you’re profiling the correct binary (local build vs /Applications). Prefer direct binary path for
```
--launch
```
.
Ensure you trigger the slow path during capture (menu open/close, refresh, etc.).
If stacks are empty, capture longer or avoid idle sections.

xcrun xctrace help record

and

xcrun xctrace help export

show correct flags.

始终确认你正在剖析的是正确的二进制文件（本地构建版本 vs /Applications目录下的版本）。使用
```
--launch
```
参数时，优先指定直接的二进制文件路径。
确保在捕获过程中触发慢路径操作（如打开/关闭菜单、刷新等）。
如果调用栈为空，延长捕获时间或避免在空闲时段捕获。

xcrun xctrace help record

和

xcrun xctrace help export

命令可查看正确的参数选项。

Included scripts

包含的脚本

```
scripts/record_time_profiler.sh
```
: record via attach or launch.
```
scripts/extract_time_samples.py
```
: export time-sample XML from a trace.
```
scripts/top_hotspots.py
```
: symbolicate and rank top app frames.

```
scripts/record_time_profiler.sh
```
：通过附加进程或启动应用的方式录制追踪。
```
scripts/extract_time_samples.py
```
：从追踪文件导出时间样本XML。
```
scripts/top_hotspots.py
```
：对应用的调用栈帧进行符号化并排序出Top热点。

Gotchas

注意事项

ASLR means you must use the runtime
```
__TEXT
```
load address from
```
vmmap
```
.
If using a new build, update the
```
--binary
```
path; symbols must match the trace.
CLI-only flow: no need to open Instruments if stacks are symbolicated via
```
atos
```
.

ASLR意味着你必须使用
```
vmmap
```
获取运行时的
```
__TEXT
```
段加载地址。
如果使用新构建的应用，更新
```
--binary
```
路径；符号必须与追踪文件匹配。
仅CLI流程：如果通过
```
atos
```
完成符号化，无需打开Instruments。