On 2/26/2011 6:03 PM, Jonathan M Davis wrote:
> On Saturday 26 February 2011 12:39:16 Andrei Alexandrescu wrote:
>> Yah, the newsgroup. The more eyes, the better.
> 
> Yeah. Technically, I would argue that this _is_ the proper place (it _is_ the Phobos list after all), but not enough people pay attention to this list. Most everyone that pays attention to any of the D newsgroups pays attention to the main D newsgroup, I think. So, anything that we want to have high visibility needs to go there, if it makes more sense organizationally for it to go elsewhere.
> 
> - Jonathan M Davis

I think the separation we have right now is a good one, worth maintaining.  This list is highly focused on the core developers and the raw mechanics of maintaining the code.  The newsgroups are more public and for more general discussion.  If the phobos list grew more general and chatty, I'd want to see phobos-dev@ or something created to re-isolate the mechanics parts.

My 2 cents,
Brad

On 2/26/11 8:06 PM, Brad Roberts wrote:
> On 2/26/2011 6:03 PM, Jonathan M Davis wrote:
>> On Saturday 26 February 2011 12:39:16 Andrei Alexandrescu wrote:
>>> Yah, the newsgroup. The more eyes, the better.
>>
>> Yeah. Technically, I would argue that this _is_ the proper place (it _is_ the Phobos list after all), but not enough people pay attention to this list. Most everyone that pays attention to any of the D newsgroups pays attention to the main D newsgroup, I think. So, anything that we want to have high visibility needs to go there, if it makes more sense organizationally for it to go elsewhere.
>>
>> - Jonathan M Davis
>
> I think the separation we have right now is a good one, worth maintaining.  This list is highly focused on the core developers and the raw mechanics of maintaining the code.  The newsgroups are more public and for more general discussion.  If the phobos list grew more general and chatty, I'd want to see phobos-dev@ or something created to re-isolate the mechanics parts.
>
> My 2 cents,
> Brad

Agreed. That stance still leaves library submissions to the newsgroup because they are of general interest. As a counterexample, a discussion about implementation policies inside the library would belong here.

Andrei

On Saturday 26 February 2011 18:06:44 Brad Roberts wrote:
> On 2/26/2011 6:03 PM, Jonathan M Davis wrote:
> > On Saturday 26 February 2011 12:39:16 Andrei Alexandrescu wrote:
> >> Yah, the newsgroup. The more eyes, the better.
> > 
> > Yeah. Technically, I would argue that this _is_ the proper place (it _is_ the Phobos list after all), but not enough people pay attention to this list. Most everyone that pays attention to any of the D newsgroups pays attention to the main D newsgroup, I think. So, anything that we want to have high visibility needs to go there, if it makes more sense organizationally for it to go elsewhere.
> > 
> > - Jonathan M Davis
> 
> I think the separation we have right now is a good one, worth maintaining. This list is highly focused on the core developers and the raw mechanics of maintaining the code.  The newsgroups are more public and for more general discussion.  If the phobos list grew more general and chatty, I'd want to see phobos-dev@ or something created to re-isolate the mechanics parts.
> 
> My 2 cents,
> Brad

Good point. But I don't see it as likely to change in either case, unless we specifically make an effort to get people to discuss stuff on this list, which I see no reason to do.

No, if there were any real changes to the lists, I'd love to stop seeing people post to the bugs list (actually, I'd argue that we should just lock it down so that you _can't_ post from it - only receive), and there are times that it would be nice if people posted stuff to D.Learn instead of D, though that's not all that big a problem (though maybe list D.Learn as first in the list of newsgroups on the site would fix that problem).

Overall, I think that things are working fairly well as they are.

- Jonathan M Davis

On Sat, 2011-02-26 at 14:54 -0500, David Simcha wrote:
> BTW, is it ok if I include your pi calculating benchmark in the benchmarks folder, too?  (I may modify it to make it slightly more idiomatic.)

No problem.

It would be interesting to see what changes you make: idiomatic is always good :-)
-- 
Russel. ============================================================================= Dr Russel Winder      t: +44 20 7585 2200   voip: sip:russel.winder at ekiga.net 41 Buckmaster Road    m: +44 7770 465 077   xmpp: russel at russel.org.uk London SW11 1EN, UK   w: www.russel.org.uk  skype: russel_winder
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: This is a digitally signed message part
URL: <http://lists.puremagic.com/pipermail/phobos/attachments/20110303/9a65ab78/attachment.pgp>

An HTML attachment was scrubbed...
URL: <http://lists.puremagic.com/pipermail/phobos/attachments/20110303/80f2f6f8/attachment.html>

An HTML attachment was scrubbed...
URL: <http://lists.puremagic.com/pipermail/phobos/attachments/20110303/673c0e69/attachment-0001.html>

On Thu, 2011-03-03 at 09:40 -0500, David Simcha wrote:
> Forgot to mention, though:  The more idiomatic/shorter way to write something like this would be to perform a reduction on a (non-parallel, lazy, random access) std.parallelism.Map.  The map function will be evaluated in parallel naturally, as the parallel reduction is performed.  Maybe this should be an example in the docs for reduce.  In your pi example:
> 
> // Nested function inside main().
> double calculateTerm(int i) {
>     immutable x = (i - 0.5) * delta ;
>     return 1.0 / (1.0 + x * x);
> }
> 
> immutable sum = taskPool.reduce!"a + b"(
>     std.algorithm.map!calculateTerm(iota(n))
> );

(The above is a slight oversimplification of the situation I have
but . . . )

Sadly this doesn't seem to work.  I tried:

  immutable pi = 4.0 * taskPool.reduce ! ( "a + b" ) ( 0.0 , taskPool.map ! ( partialSum ) ( inputData ) ) * delta ;

and this works fine showing good scaling.  However:

  immutable pi = 4.0 * taskPool.reduce ! ( "a + b" ) ( 0.0 , map ! ( partialSum ) ( inputData ) ) * delta ;

forces serialization so no speed up.

-- 
Russel. ============================================================================= Dr Russel Winder      t: +44 20 7585 2200   voip: sip:russel.winder at ekiga.net 41 Buckmaster Road    m: +44 7770 465 077   xmpp: russel at russel.org.uk London SW11 1EN, UK   w: www.russel.org.uk  skype: russel_winder
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: This is a digitally signed message part
URL: <http://lists.puremagic.com/pipermail/phobos/attachments/20110306/56358ca3/attachment.pgp>

An HTML attachment was scrubbed...
URL: <http://lists.puremagic.com/pipermail/phobos/attachments/20110306/2a765799/attachment.html>

On Sun, 2011-03-06 at 11:57 -0500, David Simcha wrote:
> Please post the full code somewhere.  The second one really should scale better, and I want to understand in context how you're parallelizing this.

No problem.  All the codes of all the variations in all the languages are in a Bazaar branch which can be branched from http://www.russel.org.uk/Bazaar/Pi_Quadrature or if you just want to browse the the URL is http://www.russel.org.uk:8080/Pi_Quadrature/

This is a simple one stage scatter/gather, that is basically a large number of additions partition to maximize use of processors.  It should be embarrassingly parallel.

I use SCons as a compilation driver so as to not have to remember lengthy command lines, but it is almost certainly the case that there are a number of assumptions in the SConstruct file about location or existence of environment variables.

-- 
Russel. ============================================================================= Dr Russel Winder      t: +44 20 7585 2200   voip: sip:russel.winder at ekiga.net 41 Buckmaster Road    m: +44 7770 465 077   xmpp: russel at russel.org.uk London SW11 1EN, UK   w: www.russel.org.uk  skype: russel_winder
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: This is a digitally signed message part
URL: <http://lists.puremagic.com/pipermail/phobos/attachments/20110306/6ebdd230/attachment.pgp>

An HTML attachment was scrubbed...
URL: <http://lists.puremagic.com/pipermail/phobos/attachments/20110306/f537c4df/attachment.html>
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: pi_d2_sequentialMapParallelReduce.d
URL: <http://lists.puremagic.com/pipermail/phobos/attachments/20110306/f537c4df/attachment.ksh>