| commit | 19c88a8dab8c926a01eadd06b4a17267cf39319d | [log] [tgz] |
|---|---|---|
| author | Jens Johansen <jensj@google.com> | Mon Aug 26 13:29:09 2024 +0000 |
| committer | dart-internal-monorepo <dart-internal-monorepo@dart-ci-internal.iam.gserviceaccount.com> | Mon Aug 26 06:33:51 2024 -0700 |
| tree | 9952add18a0e31bd2d854fc2e5a815770f0f5262 | |
| parent | da25d35859822f3889852fd19d7c5486cb2b7dbc [diff] |
[parser/CFE] Allow opting out of lazy strings; CFE opts out for body building The scanner, when creating StringTokens cuts out the substring lazily if their length is above some threshold. The work is then only done when and if we actually need the string. This makes sense for the cases where we normally do not need the string. In the CFE we scan all sources twice: Once for building the outline, and once for building the bodies. When building the bodies we in almost always actually need the string anyway (something along the lines of we don't ask for <400 out of over 400,000 when compiling the CFE itself). This CL opts the CFEs second scan (when building bodies) out of the lazy strings, copying the substrings up front, avoiding the creation of intermediary `_LazySubstring` (`_CompactLazySubstring` / `_FullLazySubstring`). With an AOT compile of the CFE, compiling itself, 50 runs gives these statistics: ``` msec task-clock:u: -1.3619% +/- 0.3329% (-57.88 +/- 14.15) page-faults:u: -1.1453% +/- 0.0162% (-1163.82 +/- 16.44) cycles:u: -1.4138% +/- 0.3433% (-248274774.52 +/- 60279949.79) instructions:u: -0.5573% +/- 0.0003% (-120171914.10 +/- 59862.46) branch-misses:u: -3.2906% +/- 1.4496% (-2192237.90 +/- 965762.85) seconds time elapsed: -1.3662% +/- 0.3338% (-0.06 +/- 0.01) seconds user: -1.3354% +/- 0.3715% (-0.05 +/- 0.01) Scavenge( new space) goes from 63 to 62 ``` 25 other runs gave these: ``` msec task-clock:u: -0.7929% +/- 0.4759% (-33.69 +/- 20.22) page-faults:u: -1.1654% +/- 0.0176% (-1184.36 +/- 17.88) cycles:u: -0.7756% +/- 0.5043% (-136122352.96 +/- 88506748.30) instructions:u: -0.5578% +/- 0.0005% (-120265633.72 +/- 115062.27) seconds time elapsed: -0.7852% +/- 0.4726% (-0.03 +/- 0.02) Scavenge( new space) goes from 63 to 62 ``` So it seems likely that new space GCs go from 63 to 62, theat the instruction count goes down by 0.55% and that it's actually around 1% faster. Change-Id: Ic462a67db7274cc8ed38df7f3ed9f41f7497fc82 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/382162 Commit-Queue: Jens Johansen <jensj@google.com> Reviewed-by: Johnni Winther <johnniwinther@google.com> https://dart.googlesource.com/sdk/+/f391b0d3e74fdd71c6598f2963d616eed84fe96a
Monorepo is:
With depot_tools installed and on your path, create a directory for your monorepo checkout and run these commands to create a gclient solution in that directory:
mkdir monorepo cd monorepo gclient config --unmanaged https://dart.googlesource.com/monorepo gclient sync -D
This gives you a checkout in the monorepo directory that contains:
monorepo/ DEPS - the DEPS used for this gclient checkout commits.json - the pinned commits for Dart, flutter/engine, and flutter/flutter tools/ - scripts used to create monorepo DEPS engine/src/ - the flutter/buildroot repo flutter/ - the flutter/engine repo out/ - the build directory, where Flutter engine builds are created third_party/ - Flutter dependencies checked out by DEPS dart/ - the Dart SDK checkout. third_party - Dart dependencies, also used by Flutter flutter/ - the flutter/flutter repo
Flutter's instructions for building the engine are at Compiling the engine
They can be followed closely, with a few changes:
goma_ctl ensure_start is sufficient.Example build commands that work on linux:
MONOREPO_PATH=$PWD if [[ ! $PATH =~ (^|:)$MONOREPO_PATH/flutter/bin(:|$) ]]; then PATH=$MONOREPO_PATH/flutter/bin:$PATH fi export GOMA_DIR=$(dirname $(command -v gclient))/.cipd_bin goma_ctl ensure_start pushd engine/src flutter/tools/gn --goma --no-prebuilt-dart-sdk --unoptimized --full-dart-sdk autoninja -C out/host_debug_unopt popd
The Flutter commands used to build and run apps will use the locally built Flutter engine and Dart SDK, instead of the one downloaded by the Flutter tool, if the --local-engine option is provided.
For example, to build and run the Flutter spinning square sample on the web platform,
MONOREPO_PATH=$PWD cd flutter/examples/layers flutter --local-engine=host_debug_unopt \ -d chrome run widgets/spinning_square.dart cd $MONOREPO_PATH
To build for desktop, specify the desktop platform device in flutter run as -d macos or -d linux or -d windows. You may also need to run the command
flutter create --platforms=windows,macos,linux
on existing apps, such as sample apps. New apps created with flutter create already include these support files. Details of desktop support are at Desktop Support for Flutter
Tests in the Flutter source tree can be run with the flutter test command, run in the directory of a package containing tests. For example:
MONOREPO_PATH=$PWD cd flutter/packages/flutter flutter test --local-engine=host_debug_unopt cd $MONOREPO_PATH
Please file an issue or email the dart-engprod team with any problems with or questions about using monorepo.
We will update this documentation to address them.
flutter commands may download the engine and Dart SDK files for the configured channel, even though they will be using the local engine and its SDK.gclient sync needs to be run in an administrator session, because some installed dependencies create symlinks.