On Tue, Oct 19, 2010 at 1:24 AM, Anne van Kesteren <ann...@opera.com> wrote: > On Mon, 18 Oct 2010 20:15:53 +0200, Jonas Sicking <jo...@sicking.cc> wrote: >> >> Without revoking the UA has to keep around the URL-string -> resource >> mapping for the lifetime of the page. Which in the world of web apps >> can be a very long time. Even worse, in the case of dynamically >> created blobs (blobbuilder, canvas.toFile/toBlob/getAsFile whatever >> we'll call it), the resource has to stay around at least on the users >> file system for the lifetime of the page. > > So we are moving the responsibility to do things right to authors? Oh joy. > Though I suppose it might just work for the most complex of applications, > where they measure things such as memory usage, etc.
Suggestions welcome. The base problem here is that we are doing resource management using a string-value rather than using a object-reference. It is provably impossible for the implementation to know if a given url is going to get used in the future (since it requires solving the halting problem). The only real solution here is to abandon the use of URLs-strings ("blob:...") and instead use some type of object which represents a reference to the blob/stream/whatever. Then make img.src, iframe.src, CSSStyleDeclaration.backgroundImage etc accept this new type in addition to a string. I think the main mitigating factor here is that as far as memory usage goes, the only thing "leaked" is an entry in a hash-table, so in the order of 50 bytes for each generated url. / Jonas