blob: 0916e07d23c57800eff65577e977f282ba52a451 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
# Incremental Install
Incremental Install is a way of building & deploying an APK that tries to
minimize the time it takes to make a change and see that change running on
device. They work best with `is_component_build=true`, and do *not* require a
rooted device.
## Building
**Option 1:** Add the gn arg:
incremental_apk_by_default = true
This causes all apks to be built as incremental (except for blacklisted ones).
**Option 2:** Add `_incremental` to the apk target name. E.g.:
ninja -C out/Debug chrome_public_apk_incremental
ninja -C out/Debug chrome_public_test_apk_incremental
## Running
It is not enough to `adb install` them. You must use a generated wrapper script:
out/Debug/bin/install_chrome_public_apk_incremental
out/Debug/bin/run_chrome_public_test_apk_incremental # Automatically sets --fast-local-dev
## Caveats
Isolated processes (on L+) are incompatible with incremental install. As a
work-around, you can disable isolated processes only for incremental apks using
gn arg:
disable_incremental_isolated_processes = true
# How it Works
## Overview
The basic idea is to side-load .dex and .so files to `/data/local/tmp` rather
than bundling them in the .apk. Then, when making a change, only the changed
.dex / .so needs to be pushed to the device.
Faster Builds:
* No `final_dex` step (where all .dex files are merged into one)
* No need to rebuild .apk for code-only changes (but required for resources)
* Apks sign faster because they are smaller.
Faster Installs:
* The .apk is smaller, and so faster to verify.
* No need to run `adb install` for code-only changes.
* Only changed .so / .dex files are pushed. MD5s of existing on-device files
are cached on host computer.
Slower Initial Runs:
* The first time you run an incremental .apk, the `DexOpt` needs to run on all
.dex files. This step is normally done during `adb install`, but is done on
start-up for incremental apks.
* DexOpt results are cached, so subsequent runs are much faster
## The Code
All incremental apks have the same classes.dex, which is built from:
//build/android/incremental_install:bootstrap_java
They also have a transformed `AndroidManifest.xml`, which overrides the the
main application class and any instrumentation classes so that they instead
point to `BootstrapApplication`. This is built by:
//build/android/incremental_install/generate_android_manifest.py
Wrapper scripts and install logic is contained in:
//build/android/incremental_install/create_install_script.py
//build/android/incremental_install/installer.py
Finally, GN logic for incremental apks is sprinkled throughout.
|
