- From: fantasai <fantasai.lists@inkedblade.net>
- Date: Tue, 1 Dec 2015 16:35:24 -0500
- To: Daniel Holbert <dholbert@mozilla.com>, Greg Whitworth <gwhit@microsoft.com>, "Tab Atkins Jr." <jackalmage@gmail.com>
- Cc: www-style list <www-style@w3.org>
On 08/20/2015 05:37 PM, Daniel Holbert wrote: > On 07/30/2015 07:33 PM, Greg Whitworth wrote: >>> >>> The >>> fact that you need to do a two pass layout to resolve them doesn't seem to >>> be hindrance at this point, are you receiving bug reports regarding poor perf >>> on flex dependent sites? > > Yes, we have received bug reports with poor performance on particular > sometimes-pathological configurations of deeply-nested flex containers. > We also encountered poor performance with a proof-of-concept experiment > about converting every element in the Firefox UI to be "display:flex". > > It's possible that some of the deeply-nested two-pass layout steps can > be optimized away with appropriate precomputation and/or re-use of > cached sizes, though, and Firefox just needs additional optimizations to > take advantage of these opportunities. So I'm not yet sure how > fundamentally-unavoidable the perf impact/blowup is from this two-pass > layout, at this point. Based on discussions with all of you, we have updated the spec to say that percentages do resolve against the automatic minimum. https://drafts.csswg.org/css-flexbox-1/#change-2015-min-auto-intrinsic-percentages Let me know if that looks good. Wrt optimization, I think you can optimistically assume that most cases won't be controlled by the min-size, and only do extra work if that isn't so. ~fantasai
Received on Tuesday, 1 December 2015 21:35:54 UTC