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digitalmars.D - Herb's Talk at NWC++ (It's interesting)

reply zz <zz zz.com> writes:
"The Concur Project: Some Experimental Concurrency Abstractions for 
Imperative Languages"

http://video.google.co.uk/videoplay?docid=7625918717318948700&q=Herb+Sutter

zz
Nov 27 2006
next sibling parent Georg Wrede <georg.wrede nospam.org> writes:
zz wrote:

 
 "The Concur Project: Some Experimental Concurrency Abstractions for 
 Imperative Languages"
 
 http://video.google.co.uk/videoplay?docid=7625918717318948700&q=Herb+Sutter


Just skimmed through this one, it's about the same as some others you 
can find on his website.

This concurrency stuff is very interesting. But I've decided I won't 
talk about it before Jan 1, 2007.

:-)
Nov 27 2006
prev sibling parent reply "Craig Black" <cblack ara.com> writes:
An elegant solution for concurrency is probably the most challenging problem 
facing modern programming languages. It may take a year or so, but I am 
confident that D will rise to the occasion here.  DMD will probably have a 
decent solution implemented far before any C++ compiler.

-Craig
Nov 27 2006
next sibling parent Lutger <lutger.blijdestijn gmail.com> writes:
Craig Black wrote:

 An elegant solution for concurrency is probably the most challenging problem 
 facing modern programming languages. It may take a year or so, but I am 
 confident that D will rise to the occasion here.  DMD will probably have a 
 decent solution implemented far before any C++ compiler.
 
 -Craig 
 


Perhaps D can then adopt Herb Sutter's slogan as a motto: re-enabling 
the free lunch...
Nov 27 2006
prev sibling parent reply Walter Bright <newshound digitalmars.com> writes:
Craig Black wrote:

 An elegant solution for concurrency is probably the most challenging problem 
 facing modern programming languages. It may take a year or so, but I am 
 confident that D will rise to the occasion here.  DMD will probably have a 
 decent solution implemented far before any C++ compiler.


The C++ committee is hard at work on improving threading support in C++. 
I figure I'll let them do the dirty work, and then we'll cherry pick the 
best! Especially since I have a hard time understanding it, and we have 
enough on our plate in the meantime.
Nov 28 2006
next sibling parent reply Sean Kelly <sean f4.ca> writes:
Walter Bright wrote:

 Craig Black wrote:

 An elegant solution for concurrency is probably the most challenging 
 problem facing modern programming languages. It may take a year or so, 
 but I am confident that D will rise to the occasion here.  DMD will 
 probably have a decent solution implemented far before any C++ compiler.


 
 The C++ committee is hard at work on improving threading support in C++. 
 I figure I'll let them do the dirty work, and then we'll cherry pick the 
 best! Especially since I have a hard time understanding it, and we have 
 enough on our plate in the meantime.


I've been keeping an eye on the discussion since... well, since it was 
the subject of speculation and ridicule on c.p.t :-p  But there are a 
lot of very capable people involved and it has started coming together 
quite nicely.  The really interesting bit in my opinion is that they're 
talking about tossing the idea of sequence points and replacing it with 
something more compatible with concurrency.  And it seems some of the 
roots of the discussion were on comp.std.c++ where a compiler writer 
(can't remember who offhand) pointed out that the C++ concept of 
sequence points had no relation to how a compiler actually compiles and 
optimizes code, so strengthening the guarantees in the sequence point 
model was not feasible.  In fact, one thing has struck me over the 
course of the committee discussions: some of the most difficult problems 
they've been grappling with (like those above) could be solved quite 
neatly by D's concept of 'volatile'.  I think this is one very 
interesting aspect of a programming language that was designed by a 
compiler writer (you) versus a committee that, by and large, has little 
understanding of the real issues involved in some of their decisions. 
That said, I do think D's volatile may be a bit too low-level for the 
average programmer, so a carefully designed memory model may turn out to 
be quite useful anyway.  But then it may also hobble compilers to such a 
degree that the opportunities for a lot of useful optimizations are 
lost, or that optimization becomes far more complicated.  I'm very 
interested to see how things turn out :-)

As for the library aspect, I think the D community already has some 
projects which are quite competitive with what is planned for C++.  And 
some of the more advanced bits, like futures, will probably make it into 
D before too long as well.  Finally, that D is a garbage collected 
language without object copy semantics makes some things possible or 
even trivial for concurrency in D that are just not so in C++.  Not to 
mention delegates and some of the other advanced features that are not 
even planned for the next iteration of C++.  So I am confident that D 
will be quite competitive with whatever comes out of C++ 0x concurrency 
on a library level, and we'll likely have it years before it gains 
traction in the C++ community.  But again, what truly interests me are 
the language changes anyway.


Sean
Nov 28 2006
parent Walter Bright <newshound digitalmars.com> writes:
Sean Kelly wrote:

 In fact, one thing has struck me over the
 course of the committee discussions: some of the most difficult problems 
 they've been grappling with (like those above) could be solved quite 
 neatly by D's concept of 'volatile'.


Wouldn't that be ironic? D's volatile is an inspiration that just came 
to me out of ignorance as I was listening to Scott Meyer's double 
checked locking presentation on the perils of code motion. I thought, 
maybe all that needs to happen is to be able to draw a horizontal line 
and disallow code motion across that line. If I knew more about 
threading, I probably would have never thought of it.

It's amazing how one's thoughts are constrained by the rut of one's 
experience.


 As for the library aspect, I think the D community already has some 
 projects which are quite competitive with what is planned for C++.  And 
 some of the more advanced bits, like futures, will probably make it into 
 D before too long as well.  Finally, that D is a garbage collected 
 language without object copy semantics makes some things possible or 
 even trivial for concurrency in D that are just not so in C++.  Not to 
 mention delegates and some of the other advanced features that are not 
 even planned for the next iteration of C++.  So I am confident that D 
 will be quite competitive with whatever comes out of C++ 0x concurrency 
 on a library level, and we'll likely have it years before it gains 
 traction in the C++ community.  But again, what truly interests me are 
 the language changes anyway.


I agree. D is way ahead even of paper *proposals* for C++, let alone 
implemented features available to programmers. With tuples D seems to 
have passed a turning point. Andrei always told me that tuples were a 
very big deal, but it's a little shocking how much of a dramatic 
improvement they offer.
Nov 30 2006
prev sibling parent "Craig Black" <cblack ara.com> writes:
"Walter Bright" <newshound digitalmars.com> wrote in message 
news:ekip5v$1igk$2 digitaldaemon.com...

 Craig Black wrote:

 An elegant solution for concurrency is probably the most challenging 
 problem facing modern programming languages. It may take a year or so, 
 but I am confident that D will rise to the occasion here.  DMD will 
 probably have a decent solution implemented far before any C++ compiler.


 The C++ committee is hard at work on improving threading support in C++. I 
 figure I'll let them do the dirty work, and then we'll cherry pick the 
 best! Especially since I have a hard time understanding it, and we have 
 enough on our plate in the meantime.


Good approach.  No need to do it yourself if they are going to solve it for 
you.  I have a hard time with concurrency too.  I think that it's something 
that you have to do for a while to really grasp well.

-Craig
Nov 29 2006