1811927 - Report non-malloc memory managed by SpiderMonkey to the profiler, e.g. wasm memory

Status: ASSIGNED

(Core :: Gecko Profiler, enhancement, P3)

Description

[Greg Tatum [:gregtatum]]

Here is an example of a profile that is marshalling around large array buffers of memory, that eventually get loaded into a wasm execution environment. GC events happen, and the JS ArrayBuffer memory disappears, but there is no evidence in the profile that this memory still exists.

https://share.firefox.dev/3kDXMcu

I believe SpiderMonkey is using mmap that is not hooked like malloc is hooked.

A couple years back I discussed this, and here are my notes from that discussion: https://docs.google.com/document/d/1JnQZ-k63D2BN6-u8cZhqZzDsj1R7vKl9nWbHeDI4oeI/edit#heading=h.x7a1vz4hyy7z

I'm not sure if the wasm memory is using the same mechanisms that were discussed in the document above.

Comment 1

[Randell Jesup [:jesup] (needinfo me)]

Attachment: Bug 1811927: Add js ArrayBuffers, WASM, and SharedMemory to profiler memory stats r=mstange!,jandem!,:jrmuizel!