On 12/14/2011 5:10 PM, Ian Hickson wrote:
On Wed, 14 Dec 2011, Jonas Sicking wrote:
On Wed, Dec 14, 2011 at 4:55 PM, Ian Hickson<i...@hixie.ch> wrote:
On Wed, 14 Dec 2011, Glenn Maynard wrote:
The problem isn't the cost of the URL mapping, it's the cost of
keeping the backing Blob around. If you drag around Google Maps for
a long time, and it used object URLs to load its tile images, it'd be
very bad if the browser had to keep every tile graphic around for the
lifetime of the page.
Browsers do keep them around for the lifetime of the page, in their
HTTP cache.
This isn't true at least for Firefox. We allow resources to be kicked
out of the HTTP cache even if the page that originally caused the
resource to be loaded is still being used.
I guess. For pages that are dealing with bazillions of images then it
makes sense to have the page discard the blobs once they're no longer in
use. But I am very skeptical about an API that makes that happen
automatically, because it really makes the API as a whole quite brittle.
Seems to me that onerror hooks are handy in this case, but that does
create more work.
I've typically used setAttribute('data-bloburl', url) when working with
images, running revoke prior to doing a new setAttribute.
I've not started using onerror: I could certainly see using onerror and
some other internal pointer, setAttribute('data-position', posinset) to
refresh a blob url, recovering it when it breaks.
That doesn't help the CSS case, however. Using automatic revocation
with CSS makes no sense at all, I think the use here is simply for
one-time img.src setters.
I also think that it can be accomplished without the Boolean, by
ensuring that revoke does not take effect until the end of the event loop.
-Charles
