sky very slow on Mac webkit based browsers

This has been brought to my attention, and I've experienced it too. I didn't realize it was an issue with the theme until someone brought it to my attention. The problem is - I have no idea what's causing it and can't figure out to fix.

Hopefully someone will help with this one.

I found a bug reported to webkit that may explain it. Perhaps Sky's full page background gradient is hitting this WebKit memory bug:

GeneratedImage::drawPattern() appears to be using more memory than necessary.

GeneratedImage::drawPattern() creates an ImageBuffer the size of a tile, then
creates an Image of the same size, which results in another copy of the data
being made. For large tiles (such as a gradient whose height is the height of
the body element), those are very large allocations. On the CG platforms, the
code can be re-worked to utilize CGPattern, with the generator being called
from the pattern callback and CG managing the memory allocation.
Experimentation (as part of investigating bug 24130) has shown that this
results in much faster painting and reduced memory use.

https://bugs.webkit.org/show_bug.cgi?id=24178

Wow! Really? Have you tried removing it?

That would explain why the problem is happening with Safari, and Chrome for Mac: both use WebKit.

I think I got it! Removing

-webkit-box-shadow: 1em 1em 5em rgba(0, 0, 0, 0.5);

from #wrapper in style.css (line 22) dramatically improved my vertical scroll speed on Safari.

I would recommend pulling that from the code. It has a nice effect for the browsers that support it. But it sounds like the performance hit isn't worth the benefit.

Adam!!! Thank you ;)

This was really bugging me and wasn't sure where to turn. I sooo appreciate you tracking this down and will get rid of it ASAP!

With some help from dvessel, we discovered that the size of the gradient is the problem. After changing the size to 1em instead of 5em, I don't even notice a hit anymore and we still get to keep the gradient :)

-webkit-box-shadow: 1em 1em 1em rgba(0, 0, 0, 0.5);

Thanks guys! I really appreciate.

This will be up as 6.x-3.8 in a few.