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Issue 3665 Allocation site pretenuring degrades performance in Ember
Starred by 17 users Project Member Reported by u...@chromium.org, Oct 30 2014 Back to list
Status: Assigned
Owner:
Cc:
HW: ----
OS: All
Priority: 2
Type: Bug

Blocked on: View detail
issue 5459
issue 3664

Blocking:
issue 2935



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v8:3664 tracks deoptimizations caused by weak references. With disabled weak references, allocation site pretenuring is the next common cause of deoptimization.

"Complex List" test at http://samsaffron.github.io/ember-performance/?ember=1.8.0 runs
- 185.11ms without weak references, with allocation site pretenuring (--js-flags="--noweak-embedded-objects-in-optimized-code --noweak-embedded-maps-in-optimized-code")
- 169.57ms without weak references and without allocation site pretenuring (--js-flags="--noweak-embedded-objects-in-optimized-code --noweak-embedded-maps-in-optimized-code --noallocation-site-pretenuring")
 
Comment 1 by u...@chromium.org, Oct 30 2014
Blocking: v8:2935
Comment 2 by habl...@google.com, Apr 29 2015
Status: Assigned
Comment 3 by wyc...@gmail.com, Nov 14 2015
Any progress on this?
Yes, months ago we tried disabling allocation site pretenuring, so that none of these deopts occur. The performance effect was negligible. Deopts occurred in those functions anyway, for other reasons.
Blockedon: 5459
Comment 6 by hablich@chromium.org, Today (15 hours ago)
Labels: Priority-2
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