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digitalmars.D - Re: shared adventures in the realm of thread-safety.

reply Jason House <jason.james.house gmail.com> writes:
Graham St Jack Wrote:

 So, what is the design of shared supposed to be then? Its time for Walter 
 to buy in and tell us where this is all going - I for one am very 
 confused right now.

Here's what I know: Bartosz's ownership scheme is delayed until at least D3 Shared code will be sequentially consistent Walter likes the idea of optimizing away memory barriers that the compiler can prove are unneeded (some barriers in synchronized sections) Bartosz is rewriting how threads are done similar to what his blogs hint at Issues that Bartosz hits with shared are fixed immediately Here's what I suspect from a number of emails: Because every class contains a monitor, Walter/dmd will treat every class as its own monitor for the purposes of optimization. I too wish Walter would advertise the design, but I think the simple fact is that he doesn't know what the design is!
Sep 16 2009
parent Graham St Jack <Graham.StJack internode.on.net> writes:
On Wed, 16 Sep 2009 08:00:40 -0400, Jason House wrote:

 Graham St Jack Wrote:
 
 So, what is the design of shared supposed to be then? Its time for
 Walter to buy in and tell us where this is all going - I for one am
 very confused right now.


somewhere, even if the details are still very fuzzy. I agree that the lofty goal of improving thread-safety for mere mortals is worthwhile, and that it won't be easy to pull off. What I was really after though is what the plan is for D2 right now. The whole shared situation in D2 looks like a mess to me, and I would like some reassurance that something simple and tidy will be happening soon.
 Here's what I know:
 • Bartosz's ownership scheme is delayed until at least D3 • Shared 

 will be sequentially consistent • Walter likes the idea of optimizing
 away memory barriers that the compiler can prove are unneeded (some
 barriers in synchronized sections) • Bartosz is rewriting how threads
 are done similar to what his blogs hint at • Issues that Bartosz hits
 with shared are fixed immediately
 
 Here's what I suspect from a number of emails: • Because every class
 contains a monitor, Walter/dmd will treat every class as its own monitor
 for the purposes of optimization.
 
 I too wish Walter would advertise the design, but I think the simple
 fact is that he doesn't know what the design is!

Sep 16 2009