On Mon, May 12, 2014 at 10:15 PM, Joshua Cranmer 🐧 <pidgeo...@gmail.com>wrote:
> On 5/12/2014 7:03 PM, Rik Cabanier wrote: > >> *Concerns* >> >> The original proposal required that a platform must return the exact >> number >> of logical CPU cores. To mitigate the fingerprinting concern, the proposal >> was updated so a user agent can "lie" about this. >> In the case of WebKit, it will return a maximum of 8 logical cores so high >> value machines can't be discovered. (Note that it's already possible to do >> a rough estimate of the number of cores) >> > > The discussion on the WHATWG mailing list covered a lot more than the > fingerprinting concern. Namely: > 1. The user may not want to let web applications hog all of the cores on a > machine, and exposing this kind of metric makes it easier for (good-faith) > applications to inadvertently do this. > Web applications can already do this today. There's nothing stopping them from figuring out the CPU's and trying to use them all. Worse, I think they will likely optimize for popular platforms which either overtax or underutilize non-popular ones. > 2. It's not clear that this feature is necessary to build high-quality > threading workload applications. In fact, it's possible that this technique > makes it easier to build inferior applications, relying on a potentially > inferior metric. (Note, for example, the disagreement on figuring out what > you should use for make -j if you have N cores). Everyone is in agreement that that is a hard problem to fix and that there is no clear answer. Whatever solution is picked (maybe like Grand Central or Intel TBB), most solutions will still want to know how many cores are available. Looking at the native platform (and Adobe's applications), many query the operating system for this information to balance the workload. I don't see why this would be different for the web platform. _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
