Does anyone have a good reference for all of the --js-flags="" that can be used in Chrome at the mand line, for Windows?

For performance testing, I'm currently using: chrome.exe --no-sandbox --js-flags="--trace-deopt --trace-opt"

But, I'd like to know if there are other flags that will help illuminate a problem I'm having.

Specifically, other's have referenced --trace-bailout, but that one doesn't seem to work; it's unrecognized by Chrome; I'd love to see which functions aren't being optimized by Turbofan.

Does anyone have a good reference for all of the --js-flags="" that can be used in Chrome at the mand line, for Windows?

For performance testing, I'm currently using: chrome.exe --no-sandbox --js-flags="--trace-deopt --trace-opt"

But, I'd like to know if there are other flags that will help illuminate a problem I'm having.

Specifically, other's have referenced --trace-bailout, but that one doesn't seem to work; it's unrecognized by Chrome; I'd love to see which functions aren't being optimized by Turbofan.

• javascript
• windows
• google-chrome
• v8

2 Answers 2

V8 developer here. The authoritative list of V8 flags is the source: https://chromium.googlesource./v8/v8/+/master/src/flags/flag-definitions.h#188 When that file has, e.g., DEFINE_BOOL(es_staging, ...), then the corresponding mand-line syntax in Chrome would be --js-flags="--es-staging".

I'd love to see which functions aren't being optimized by Turbofan.

Turbofan optimizes all functions, assuming they run long enough. (Many years ago, there was a set of features that Crankshaft couldn't optimize; those days are long gone, Turbofan supports everything.)

Here's a suggestion. I had no idea there were so many options!

https://peter.sh/experiments/chromium-mand-line-switches/ (Last automated update occurred on 2019-08-12.)