cc: Don't discard tiles unless memory is low

cc: Don't discard tiles unless memory is low

The TileManager will discard anything about 4k pixels
out of the viewport. This will keep already-painted
content around until memory pressure kicks it out.

Of note is that painting content outside of the inflated
rect isn't explicitly disabled by this patch (that can
happen, it's just unlikely).

Add a list of the live tiles and only remove from them
when a previously-live tile is no longer in the inflated
rect and doesn't have a Gpu resource.

BUG=176643

[ccameron, 2013-02-16 16:35:09]

This is a cleaned-up version of the patch to improve scrollback performance.

The down-sides to keeping previously-painted content around is that we have to
keep computing the priorities of those tiles, which isn't free.

This patch also doesn't contain the previously-discussed change of making
EVENTUALLY mean "don't paint, but don't discard" because it seemed risky to me.
If that is desirable, I can add it back in.

[anagy4698, 2013-02-16 18:46:44]

*ha kevés a memória ?,,,,,.*M cc/tile_manager.cc!.


2013/2/16 <ccameron@chromium.org>

> Reviewers: nduca, danakj, enne,
>
> Message:
> This is a cleaned-up version of the patch to improve scrollback
> performance.
>
> The down-sides to keeping previously-painted content around is that we
> have to
> keep computing the priorities of those tiles, which isn't free.
>
> This patch also doesn't contain the previously-discussed change of making
> EVENTUALLY mean "don't paint, but don't discard" because it seemed risky
> to me.
> If that is desirable, I can add it back in.
>
> Description:
> cc: Don't discard tiles unless memory is low
>
> The TileManager will discard anything about 4k pixels
> out of the viewport. This will keep already-painted
> content around until memory pressure kicks it out.
>
> Of note is that painting content outside of the inflated
> rect isn't explicitly disabled by this patch (that can
> happen, it's just unlikely).
>
> Add a list of the live tiles and only remove from them
> when a previously-live tile is no longer in the inflated
> rect and doesn't have a Gpu resource.
>
> BUG=176643
>
>
> Please review this at
https://codereview.chromium.**org/12280021/<https://codereview.chromium.org/1...
>
> SVN Base:
svn://svn.chromium.org/chrome/**trunk/src<http://svn.chromium.org/chrome/trunk/src>
>
> Affected files:
>   M cc/picture_layer_tiling.h
>   M cc/picture_layer_tiling.cc
>   M cc/tile_manager.cc
>
>
>


-- 
anagy4698@gmail.com.