Now, Google's engineers seem to be working on an experimental flag designed to optimize the browser resource usage. Chromium developers can manage resource using “Never Slow Mode”.
Caps do not apply to workers and size caps are lifted for resources loaded from Service Worker Cache Storage.
"Never-Slow Mode", as the company's engineers are calling it on the Chromium Gerrit, would cap the resource usage of pages and heavy scripts.
The new mode places tight limitations on Web content in an effort to make its performance more robust and predictable.
Developer Alex Russell describes,
Adds `--enable-features=NeverSlowMode` to enforce per-interaction budgets designed to keep the main thread clean (design doc currently internal).
Currently blocks large scripts, sets budgets for certain resource types (script, font, CSS, images), turns off document.write(), clobbers sync XHR, enables client-hints pervasively, and buffers resources without `Content-Length` set. Budgets are reset on interaction (click/tap/scroll). Long script tasks (> 200ms) pause all page execution until the next interaction.
The details of the new mode aren't 100% clear and as it is only an internal proposal. With a little more time and polish, it could turn into a real feature that power users who want their browser to run as efficiently as possible would really appreciate.