[Lldb-commits] [lldb] DynamicLoaderDarwin load images in parallel (PR #110439)

[Jason Molenda via lldb-commits]

jasonmolenda wrote:

For completeness sakes, here's what I see for parallel+preload PR 110646 with llvm-project main (no swift demangling) attaching to Slack (nearly all libraries in the shared cache)

```
% time build.release.parallel-with-preload//bin/lldb -x -b  -o 'pro att -n Slack' -o 'det'
4.643u 2.672s 0:10.63 68.7%	0+0k 0+0io 3277pf+0w
4.509u 2.120s 0:09.39 70.5%	0+0k 0+0io 148pf+0w
4.509u 2.120s 0:09.39 70.5%	0+0k 0+0io 148pf+0w
4.519u 2.124s 0:09.38 70.6%	0+0k 0+0io 104pf+0w
```
(showed the results for 4 runs)
and with the multithreading enabled

```
% time build.release.parallel-with-preload/bin/lldb -x -b -O 'settings set plugin.experimental.dynamic-loader.darwin.enable-parallel-image-load true' -o 'pro att -n Slack' -o 'det'
6.635u 3.840s 0:06.30 166.1%	0+0k 0+0io 104pf+0w
6.635u 3.840s 0:06.30 166.1%	0+0k 0+0io 104pf+0w
6.573u 3.776s 0:06.18 167.3%	0+0k 0+0io 104pf+0w
6.601u 3.781s 0:06.20 167.4%	0+0k 0+0io 104pf+0w
```

and github main unmodified

```
% time build.release/bin/lldb -x -b  -o 'pro att -n Slack' -o 'det'
4.571u 2.311s 0:09.55 72.0%	0+0k 0+0io 3258pf+0w
4.535u 2.112s 0:09.35 71.0%	0+0k 0+0io 146pf+0w
4.581u 2.193s 0:09.52 71.1%	0+0k 0+0io 103pf+0w
4.554u 2.178s 0:09.54 70.4%	0+0k 0+0io 103pf+0w
```

https://github.com/llvm/llvm-project/pull/110439