On Tue, Jun 12, 2012 at 10:47 PM, Stewart Mckinney <lordma...@gmail.com>wrote:
> A key thing to understand about v8 is that it JIT compiles your Javascript > straight into machine language ( via the meta-lang pipeline: Crankshaft-> > Helium-> Lithium ). This makes context switches far, far more costly, > because v8 does not actually deal directly ( much ) with its abstractions. > It does use them in formulation but then discards them when no longer > needed. This means if you go a-fetching v8 has to do some searching and > constructing before it can make your switch, unless you've asked v8 to > 'hold onto' something ( which in turn, slows down the VM slightly via the > GC and forces some parts of the VM to not optimize because your essentially > telling the interpreter "this is volatile" ). This is part of the reason > why v8 encourages you to use Local Handles whenever possible. > > The smackdown here isn't that hard - your looking at about 0.00032ms or > so ( off the top of my head ) - but you take an array of say, a million > elements, and there you go. Suddenly your looking at 1/3 seconds time just > to iterate over a massive JS array in C++. > Sure, but IIRC neither NumPy nor PDL concepts of Arrays/Vectors/whatever are strictly language native. So it's basically the same as a Buffer. (sorry I guess this should be another thread). -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. To post to this group, send email to nodejs@googlegroups.com To unsubscribe from this group, send email to nodejs+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/nodejs?hl=en?hl=en
