- From: Drew Wilson <atwilson@google.com>
- Date: Wed, 21 Jul 2010 13:38:13 -0700
On Wed, Jul 21, 2010 at 1:11 PM, Ryan Heise <ryan at ryanheise.com> wrote: > > > For all of the reasons above, I would like to see something like threads > in Javascript. Yes, threads give rise to race conditions and deadlocks, > but this seems to be in line with Javascript's apparent philosophy of > doing very little static error checking, and letting things just happen > at runtime (e.g. nonexistent static type system). In other words, this > may be simply a case of: yes, javascript allows runtime errors to > happen. Is not allowing deadlocks important enough that we should make > it impossible for a certain class of algorithms to exploit multi-core > CPUs? > Rather than trying to shoehorn concurrent functionality into Javascript (where many implementations don't support multi-threaded access down at the VM level anyway, so the obstacles to implementation seem fairly large) it seems like a better option is to use a different language entirely. > > Before I sign off, there is one more feature which (correct me if I'm > wrong) is lacking from the current specification. There is currently no > way for a program to find out how many cores are present in the host > system. Without this, there is no way to know how many Web Workers to > create for an algorithm that could easily be parallelised to any number > of Web Workers / threads. Even, say, a parallel quicksort should not > just create a new thread for each recursive invocation, as deep as it > goes. For efficiency, this thread creation should stop as soon as enough > threads have been created to match the number of physical cores. After > this point, each core should handle its load by reverting to a > single-threaded quicksort. > There have been a few discussions on this issue - for example: http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2009-November/024058.html http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2009-November/023993.html Not sure if any conclusions were drawn - I think we may have kept this open as an option for v2 of the spec. > > -- > Ryan Heise > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.whatwg.org/pipermail/whatwg-whatwg.org/attachments/20100721/d4bdb3f9/attachment.htm>
Received on Wednesday, 21 July 2010 13:38:13 UTC