1807506 - Implement system.memory

Status: ASSIGNED

(WebExtensions :: General, enhancement, P5)

Description

[Gregory Pappas [:gregp]]

https://developer.chrome.com/docs/extensions/reference/system_memory/

Comment 1

[Gregory Pappas [:gregp]]

Attachment: Bug 1807506 - Implement system.memory r?mkaply!

Depends on D165499

Comment 2

[Rob Wu [:robwu]]

What are the use cases for this API?

Bug 1738348's justification is basically "because this single extension happens to be calling the API". That is not a use case; some extensions/programs request as much data as possible, for fingerprinting or debugging purposes. What we're actually looking for here is to see whether there is functionality not possible without this API.

Comment 3

[Gregory Pappas [:gregp]]

(In reply to Rob Wu [:robwu] from comment #2)

What are the use cases for this API? What we're actually looking for here is to see whether there is functionality not possible without this API.

I wrote this patch because my school uses ProctorU. ProctorU is very common (in the United States, at least) and I do think web compatibility is enough of a justification. I can try to think of some use cases, let's see:

• An extension could decide whether or not to do some memory intensive operation based on this info. e.g. If the user only has 4 gigabytes of ram, use the disk instead of memory to prevent crashing the browser.
• An extension could use this information to tune heuristics for when to flush a cache.
• I could see this being useful for extensions that maintain a lot of state (I'm vaguely imagining something with video) that want to decide if they should recompute that state or store it in memory. (Service workers/non-persistent background pages).
• There's probably someone out there that wants/needs to aggressively reduce Firefox's memory usage. So I can imagine someone creating an extension that uses this info to augment the existing memory unload heuristics built into Firefox and discard tabs. Imaginary scenario (involves bug 1809094): An extension that adds a tab context menu item to prevent unloading of a tab. This extension includes ability to optionally ignore the user, and reset their choice, if availableCapacity is below some arbitrary number.

That said, I'm not a creative person at all, and it's possible I'm missing some obvious use case.