731566 - Slow performance on CoffeePhysics

Status: RESOLVED DUPLICATE of bug 732471

(Core :: JavaScript Engine, defect)

Description

[Jeff Muizelaar [:jrmuizel]]

I'm seeing this on the profiling branch on OS X which doesn't seem to be using jemalloc. I took a look in Instruments and it looks this might be caused by us contending on malloc while releasing the garbage. Either way, this demo seems to be hard on our gc. FWIW, it runs much better in Chrome.

Comment 1

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

Could you post some of the GC log entries from the error console (with javascript.options.mem.log enabled)? On Linux I'm getting 12ms compartment GCs, which is actually pretty awesome. We've seen problems like this on Macs before, but nothing reproducible.

Comment 2

[Andrew McCreight [:mccr8]]

This is what I get on Nightly.

GC(T+41.9) TotalTime: 4.0ms, Type: compartment, MMU(20ms): 79%, MMU(50ms): 91%, Reason: TOO_MUCH_MALLOC, +chunks: 0, -chunks: 0
mark: 2.2, mark-roots: 1.3, mark-other: 0.0, sweep: 1.4, sweep-obj: 0.1, sweep-script: 0.0, sweep-shape: 0.0, discard-code: 0.0, discard-analysis: 0.3, xpconnect: 0.7, deallocate: 0.0

GC(T+31.9) TotalTime: 3.8ms, Type: compartment, MMU(20ms): 80%, MMU(50ms): 92%, Reason: TOO_MUCH_MALLOC, +chunks: 0, -chunks: 0
mark: 2.0, mark-roots: 1.1, mark-other: 0.1, sweep: 1.4, sweep-obj: 0.0, sweep-script: 0.0, sweep-shape: 0.0, discard-code: 0.0, discard-analysis: 0.3, xpconnect: 0.7, deallocate: 0.0

GC(T+73.0) TotalTime: 4.8ms, Type: compartment, MMU(20ms): 75%, MMU(50ms): 90%, Reason: TOO_MUCH_MALLOC, +chunks: 0, -chunks: 0
mark: 2.5, mark-roots: 1.5, mark-other: 0.1, sweep: 1.8, sweep-obj: 0.1, sweep-string: 0.0, sweep-script: 0.0, sweep-shape: 0.0, discard-code: 0.0, discard-analysis: 0.5, xpconnect: 0.9, deallocate: 0.0

Comment 3

[Andrew McCreight [:mccr8]]

Pauses got a little longer:

GC(T+167.5) TotalTime: 6.1ms, Type: compartment, MMU(20ms): 69%, MMU(50ms): 87%, Reason: TOO_MUCH_MALLOC, +chunks: 0, -chunks: 0
mark: 3.0, mark-roots: 2.0, mark-other: 0.1, sweep: 2.4, sweep-obj: 0.0, sweep-script: 0.0, sweep-shape: 0.0, discard-code: 0.0, discard-analysis: 0.4, xpconnect: 1.4, deallocate: 0.0

Comment 4

[Andrew McCreight [:mccr8]]

I get 12fps on Nightly and 43-ish on a release version of Chrome.

Comment 5

[David Mandelin [:dmandelin]]

To me it looks like the biggest problem is slow frame rate. GC may be an issue as well.

Comment 6

[Giorgio Maone [:ma1]]

I noticed it this morning. 
I get 4 fps on Nightly and 60 fps on Chrome.

According to Firebug's profiler, JavaScript seems to spend most of its time (63%) in http://soulwire.co.uk/coffeephysics/compiled/behaviour/Collision.js at line 20.