Great, thanks! That article was exactly what I had in mind. :) - Brian Gesiak
On Sat, Dec 17, 2016 at 2:47 PM, Mark Lacey <mark.la...@apple.com> wrote: > > On Dec 17, 2016, at 11:13 AM, Brian Gesiak via swift-dev < > swift-dev@swift.org> wrote: > > Hello all! > > I really enjoyed Chris Lattner's slides from his talk at IBM < > http://researcher.watson.ibm.com/researcher/files/us-lmandel/lattner.pdf > >. > > The speaker notes mention ARC: > > "There are two principle downsides to ARC that people cite: one is the > need for atomic increment/decrements, which can be slow." [...] "The > performance problems it can cause are real in some important cases" > > Can someone point me to a good resource that explains these problems? > > > This might be a good starter post: https://fgiesen. > wordpress.com/2014/08/18/atomics-and-contention > > I guess atomic reference count changes create overhead in multithreaded > applications? > > > There is overhead even in single-threaded applications, as the post above > discusses. The overhead depends very much on the details of the particular > microarchitecture. > > Are there more detailed explorations into this topic? > > > If you’re looking for something Swift- or ARC-specific I don’t know of > anything. > > Mark > >
_______________________________________________ swift-dev mailing list swift-dev@swift.org https://lists.swift.org/mailman/listinfo/swift-dev
