One area where D has the edge

[Paulo Pinto via Digitalmars-d]

On Tuesday, 27 January 2015 at 15:09:36 UTC, Laeeth Isharc wrote:
>> I cannot speak about small team experiences. Our projects 
>> usually take around 30+ developers.
>
> That it is a decent sized team to have to coordinate and it 
> puts emphasis on very different questions.  The context I am 
> thinking of is much leaner - more like special forces than the 
> regular army (I mean in terms of flexibility and need to 
> respond quickly to changing circumstances) - although the sums 
> at stake are likely comparable to larger teams (the area is 
> hedge fund portfolio management).
>
>> In terms of server applications, yes when the applications are 
>> deployed usually the memory usage might not be optimal.
>
> For you that is less important, and I suppose that comes from 
> the intrinsic nature of the situation.  You have beefy machines 
> serving many users, I suppose?  I am thinking of a purpose 
> where there are only a handful of users, but the data sets may 
> be larger than we are used to working with, requiring more work 
> than just plain map reduce, and where rapid iteration and 
> prototyping is important.  Also to minimize cognitive overload 
> and complexity.
>
> A friend has written an article on big data in finance for 
> Alpha magazine, and I will post a link here once it has been 
> published.
>  One problem in economics is you have to forecast the present, 
> because the numbers are published with a lag and themselves 
> reflect decisions taken months previously.  But markets are 
> forward looking and discount a future that may be imagined but 
> cannot be understood based only on hard facts.
>
> So we need all the help we can get, particularly during an 
> epoch where things change all the time,  (eurchf fx rate moved 
> forty percent in a day...). Bridgewater have taken the work of 
> Hal Varian and applied it to use media and web analytics to get 
> a good live cut of economic activity and inflation.  Although 
> it is not a tough problem theoretically, people don't actually 
> do as much as they could yet - I think finance is behind tech 
> companies, but they are catching up.  Another fund that my 
> friend writes about uses employee sentiment to pick stocks to 
> be long and short of - they manage a few billion and have done 
> quite well.
>
>> However that is why profiling and language knowledge is 
>> required.
>
> Yes, I can imagine, and it sounds like not just that Java is 
> the best option for you, but perhaps the only viable one.  I am 
> curious though - what do you think the memory footprint is as a 
> ratio to C++ before and after fine tuning?  And what proportion 
> of development time does this take?


Actually we use more than just Java.

JVM languages, .NET languages, C++ (only on the realm of 
JNI/PInvoke/COM), JavaScript

Memory optimizations only take place if really requested by the 
customer,
from their acceptance tests, which is seldom the case.

Usually one to two sprints might be spent.


>
>> Fine tuning a Java application is no different than other 
>> compiled languages, it just requires to know which knobs to 
>> turn.
>
> I liked a quote by a certain C++ guru talking about the 
> experience of a Facebook, to the effect that a sensible first 
> draft written in C++ would perform decently, whereas this was 
> not true always of other languages.  Now their trade off 
> between programmer productivity and execution efficiency is 
> extreme, but is this merely an edge case of little relevance 
> for the rest of us, or is it a Gibsonian case of the future 
> being already here, and just not evenly distributed?  I am no 
> expert, but I wonder if the latter may be more true than 
> generally appreciated.
>
>> For example, foreach allocates and a simple for does not, so 
>> choose wisely how to iterate.
>
> Would love to hear any other insights you have on this topic.  
> There ought to be a FAQ on getting along with the GC for fun 
> and profit.

Java ONE, Skills Matter and Microsoft BUILD have performance talks
every now and then.

Then there is the mechanical sympathy blog and mailing list.

http://mechanical-sympathy.blogspot.de/

>
>> The thing that Java still looses in memory management, even in 
>> commercial JVMs, is lack of value types since escape analysis 
>> algorithms are not very aggressive, but support is being 
>> designed and will land partially in Java 9 and Java 10 time 
>> frame.
>
> That was my real point - and that it does really matter in some 
> areas, and that these are growing very quickly.  (I appreciate 
> that someone reading my post quickly would see the 15% power 
> thing and focus on that, which was not so much my point - 
> although I am still suspicious of the idea that Java will 
> always keep up with native code without doing a lot of extra 
> work).
>
> People on the Slashdot thread were saying what is the point of 
> D.
>  But the way I saw it, where is the real competition for my use 
> case?  I can't be extravagant with memory, but I still need 
> rapid development and productivity.  We all have a tendency to 
> think that what we know from experience and reading is the full 
> picture, but the world is a big place, and something needs to 
> appeal to someone to grow, not necessarily to oneself personally
>
> The C++ integration is the remaining piece.  Otherwise it is 
> like the old Soviet Union - this is the factory that makes the 
> steel that builds the factory that makes the steel that... so 
> that Vladimir may have a new car.  Ie one spends too much time 
> in roundabout investment before one actually reaps the benefit 
> of higher productivity.
>
>
>> So by Java 10 according to the planned features, there will be 
>> value types and even the open source JVM will have some form 
>> of JIT cache. Including the large amount of available 
>> libraries.
>>
>> As for D, it surely has its place and I am looking forward to 
>> language adoption.
>
>
> Out of interest, what do you see as characterising this place 
> (abstracting away from things that are not perfect now, but 
> will probably be fixed in time)?  And in an enterprise 
> environment, what would you use D for today?
>
>
> Laeeth.


To be honest I don't see a place on the enterprise for my type of 
work.

As a language geek, I hang around in multiple language forums and 
I like D, because I got to appreciate systems programming with 
memory safe programming languages back in the 90's.

Our projects are usually based on distributed computing using 
JVM/.NET stacks, using mainly Oracle and MS SQL Server, web 
services, HADOOP, Akka(.NET).

Devops like to be able to use the respective management consoles 
on the servers across the network.

Desktop applications tend to be built on top of Eclipse 
RCP/Netbeans, WPF or plain Web.

The mobile space is covered with Web applications, Cordova or 
Xamarin.

This is my little world, but I imagine D being usable in startups 
or companies not constrained by other language tech stacks.


--
Paulo