1947756 - 73% tenuring rate on modified Codepen Demo (https://codepen.io/Mikhail-Bespalov/pen/dPyyZed?editors=1010), and Firefox uses 800MB-1.2GB RAM. Chrome uses 200MB

Status: NEW

(Core :: JavaScript: GC, task, P2)

Description

[Mayank Bansal]

Open the attached testcase (original at https://codepen.io/Mikhail-Bespalov/pen/dPyyZed?editors=1010. I changed the code so that the minimum grid size is 1)
Slide the grid-size slider all the way to the left ("1" value)

AR: https://share.firefox.dev/41dekuQ

We use 800MB-1.2gb RAM. Chrome takes 200MB.

Comment 1

[Mayank Bansal]

Attachment: index.html

Comment 2

[Iain Ireland [:iain]]

It looks like we have a huge number of very small nursery GCs that look like this:

Reason: NURSERY_MALLOC_BUFFERS
Bytes tenured: 192B / 280B (69%)
Cells tenured: 3.0 / 5.0 (60%)
Bytes used: 280B / 256KB (0.1%)
Nursery allocations since last minor GC: 5.0 / 9.0 (56%)

Looking at the code, I think we're allocating a big Float32Array in generateHalftone every frame, so we're hitting our mallocedBufferBytes capacity very quickly.

Comment 3

[Jon Coppeard (:jonco)]

We don't resize the nursery based on malloc bytes usage in the same way as we do for space used in the nursery itself. This would likely help here.

Comment 4

[Mayank Bansal]

Latest: https://share.firefox.dev/46aYvq1

Comment 5

[Mayank Bansal]

(In reply to Jon Coppeard (:jonco) from comment #3)

We don't resize the nursery based on malloc bytes usage in the same way as we do for space used in the nursery itself. This would likely help here.

Worth filing a bug for posterity?