[webkit-dev] Discussing bug 98539 - Refactor resource loading to allow for out-of-process loading and memory caching

[Adam Barth]

On Mon, Oct 8, 2012 at 6:21 PM, Maciej Stachowiak <mjs at apple.com> wrote:
> On Oct 8, 2012, at 5:28 PM, Adam Barth <abarth at webkit.org> wrote:
>> On Mon, Oct 8, 2012 at 2:17 PM, Brady Eidson <beidson at apple.com> wrote:
>>> On Oct 8, 2012, at 12:17 PM, Adam Barth <abarth at webkit.org> wrote:
>>>>
>>>> Would there be any design or implementation constraints on WebCore?
>>>> For example, would WebCore need to understand any concurrency or
>>>> performance issues caused by the memory being shared between
>>>> processes?
>>>
>>> For now we think the answer is no, or that any parts that do need to be concerned to be wholly encapsulated within the support for the client model.
>>
>> Ok.  If there are no design implications for WebCore, then I don't
>> have a problem with this work continuing.
>>
>> Based on my experience with this topic in Chromium, I believe you're
>> over-engineering, but if you're unwilling to share your data, I doubt
>> further discussion with cause either of us to change our minds.
>
> You can expect that we'll collect and share some data as the work progresses. The fact is that we don't have really great data to share yet, we are still in an exploratory phase. If you have any past data to share, we'd love to look at it.

Unfortunately, I don't have the data from our previous experiments anymore.

> One preliminary finding of ours is that different web pages fairly often load identical resource bodies from different URLs. We expect possible benefits from sharing the body data of resources in memory even if we cannot share the URL or response headers.
>
> You can also expect that we won't push forward blindly on this effort if data ultimately shows it to be a bad idea, or in general not worth the complexity.

As I mentioned in bugs.webkit.org, we did our experiments a number of
years ago, and it's certainly possible that the web has changed (e.g.,
social widgets have gained a lot of popularity in the intervening
time).  Maybe we should run some experiments as well and reconsider
Chromium's approach.

Adam