New issue
Advanced search Search tips

Issue 898932 link

Starred by 1 user

Issue metadata

Status: Archived
Owner:
Closed: Jan 3
Cc:
Components:
EstimatedDays: ----
NextAction: ----
OS: ----
Pri: 2
Type: Bug


Previous locations:
v8:8371


Sign in to add a comment

WebAssembly app start-up is slower with Liftoff

Reported by bu...@sketchup.com, Oct 25

Issue description

Version: Chrome Canary 72.0.3591.0, not sure what v8 version.
OS: Tested on Windows 10
Architecture: x64

Our WebAssembly application (SketchUp) is overall slower to start up (by 20-30%) with the baseline compiler enabled. We built a minimal sandbox to help diagnose this case:

https://sandboxchrome-app.sketchup.com

We traced the app (using chrome://tracing, v8 and v8.wasm checked) with and without the baseline compiler enabled. Screenshots for the traces are attached. It seems the TurboFan threads are competing with the main JS thread and slowing down our app initialization, leading to a slower observed startup time overall. This is on a 4-core hyper-threaded Core i7 CPU.

Perhaps the turbofan threads could be throttled back a bit, leaving more resources available for the app code?

Thanks and regards,
Bugra Barin

 
Canary_Liftoff_disabled.png
86.2 KB View Download
Canary_Liftoff_enabled.png
91.9 KB View Download
Project: chromium
Moved issue v8:8371 to now be  issue chromium:898932 .
Cc: clemensh@chromium.org titzer@chromium.org jarin@chromium.org
Components: Blink>JavaScript>WebAssembly
Labels: Pri-2
Status: Available (was: Untriaged)
Owner: clemensh@chromium.org
Status: Assigned (was: Available)
Thanks for the report and the minimal sandbox!

Liftoff takes surprisingly long here, nearly as long as TurboFan. Will take a look tomorrow.
Cc: hablich@chromium.org
I tried to reproduce this, but get a totally different picture. Liftoff takes ~190ms, while Turbofan takes ~1860ms (see attached picture).
I tested in the lasted dev version "72.0.3590.0 (Official Build) dev (64-bit)" on Linux.
I also tried a 32-bit Canary on Windows 10 ("Version 72.0.3592.0 (Official Build) canary (32-bit)"), and it looks similar (everything is a bit slower).

Does anyone have an idea what could be causing the numbers reported in #0?
72.0.3590.0 (Official Build) dev (64-bit).png
80.1 KB View Download
Interesting. One difference I see is that yours has more threads running. Could it be related to CPU capabilities? I am testing on Core i7-4980 2.8GHz laptop with 16GB memory. Has 4 cores (8 threads).

Status: Archived (was: Assigned)
Closing because of inactivity.

Sign in to add a comment