Booting unit tests run (ex.: test.unit.js) is slow #2094
Description
These are the logs from my Windows laptop (Win 7 64 bits, i5-4310U @ 2.0Ghz, 8Gb RAM, SSD):
Dart SDK detected
[14:10:20] Using gulpfile d:\Github\angular_mlaval\gulpfile.js
[14:10:20] Starting 'build/clean.js'...
[14:10:21] Finished 'build/clean.js' after 490 ms
[14:10:21] Starting 'build.js.dev'...
[14:10:21] Starting 'build/clean.tools'...
[14:10:21] Finished 'build/clean.tools' after 1.28 ms
[14:10:21] Starting 'build.tools'...
[14:10:21] Starting '!build.tools'...
[14:10:24] Finished '!build.tools' after 3.75 s
[14:10:24] Finished 'build.tools' after 3.75 s
[14:10:24] Starting 'broccoli.js.dev'...
[14:10:24] Starting '!broccoli.js.dev'...
Tree diff: DiffingTraceurCompiler, 81ms, 10 changes (files: 10, dirs: 232)
Tree diff: DiffingTSCompiler, 100ms, 401 changes (files: 401, dirs: 232)
Tree diff: DiffingTraceurCompiler, 103ms, 411 changes (files: 411, dirs: 127)
Tree diff: DestCopy, 267ms, 2423 changes (files: 2423, dirs: 260)
Slowest Trees | Total
----------------------------------------------+---------------------
DiffingTSCompiler | 22538ms
DiffingTraceurCompiler | 11069ms
TreeStabilizer | 4477ms
DestCopy | 4165ms
Slowest Trees (cumulative) | Total (avg)
----------------------------------------------+---------------------
DiffingTSCompiler (1) | 22538ms
TreeMerger (7) | 13469ms (1924 ms)
DiffingTraceurCompiler (2) | 11484ms (5742 ms)
Funnel (69) | 8421ms (122 ms)
TreeStabilizer (4) | 6949ms (1737 ms)
DestCopy (1) | 4165ms
[14:11:32] Finished '!broccoli.js.dev' after 1.12 min
[14:11:32] Finished 'broccoli.js.dev' after 1.12 min
[14:11:32] Starting 'build/checkCircularDependencies'...
[14:11:32] Finished 'build/checkCircularDependencies' after 377 ms
[14:11:32] Starting 'check-format'...
[14:12:34] Finished 'check-format' after 1.03 min
[14:12:34] Finished 'build.js.dev' after 2.22 min
[14:12:34] Starting 'test.unit.js'...
[14:12:34] Starting '!test.unit.js/karma-server'...
[14:12:37] Finished '!test.unit.js/karma-server' after 2.08 s
INFO [karma]: Karma v0.12.31 server started at http://localhost:9876/
INFO [launcher]: Starting browser ChromeCanary
WARN [watcher]: Pattern "d:/Github/angular_mlaval/modules/angular2/src/test_lib/shims_for_IE.es6" does not match any file.
[14:12:37] Starting '!broccoli.js.dev'...
Tree diff: DiffingTraceurCompiler, 96ms, 0 changes (files: 10, dirs: 232)
Tree diff: DiffingTSCompiler, 102ms, 0 changes (files: 401, dirs: 232)
Tree diff: DiffingTraceurCompiler, 81ms, 0 changes (files: 411, dirs: 127)
Tree diff: DestCopy, 622ms, 0 changes (files: 2423, dirs: 260)
Slowest Trees | Total
----------------------------------------------+---------------------
TreeStabilizer | 7227ms
TreeMerger | 4126ms
Funnel | 3358ms
Funnel | 3288ms
TreeMerger | 3073ms
TreeMerger | 2678ms
TreeMerger | 2545ms
Slowest Trees (cumulative) | Total (avg)
----------------------------------------------+---------------------
TreeMerger (7) | 16608ms (2372 ms)
TreeStabilizer (4) | 11377ms (2844 ms)
Funnel (69) | 10741ms (155 ms)
[14:13:20] Finished '!broccoli.js.dev' after 43 s
[14:13:20] Starting '!test.unit.js/karma-run'...
[14:13:22] Finished '!test.unit.js/karma-run' after 1.98 s
INFO [Chrome 45.0.2421 (Windows 7)]: Connected on socket wdtHkb5sSbNSGx5FfMND with id 65876799
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