> 
> What does this code do? It looks like a ThreadPool use case but I might be wrong.
> 

I tried to recursively make an object distribute its calculations. The calculations should take at least a minute.

On Sat, 10 Jan 2009 07:32:43 +0300, yes <yes@no.com> wrote:

>>
>> What does this code do? It looks like a ThreadPool use case but I might be wrong.
>>
>
> I tried to recursively make an object distribute its calculations.
> The calculations should take at least a minute.


Hm... I guess I understand now, you need a task parallelization, right?

In order to do this, you usually separate the task into several independent sub-tasks, put into a queue and wait until it is finished.

For example, we have a list of files to download from remote server. For each file, we create a new connection and retrieve it independently (and, possibly, out of order):

import tango.core.ThreadPool;

void execute()
{
   auto pool = new ThreadPool!(string)(10); // create a thread pool with 10 threads
   string[] fileList = loadFileList();
   foreach (string filePath; fileList) {
       pool.append(&download, filePath);   // append the task
   }

   pool.finish(); // wait until all the tasks complete
}

void download(string fileName)
{
   // ...
}

In this example, I create a lot of threads (more than hardware runs concurrently) because the CPU is not a bottleneck.
You may experience different results in different CPU workaload, though.

Hope that helps.

Does Phobos also do threadpools?

Somehow I liked the idea of an Object like agent smith, just duplicate yourself when the task is too big. ( ^_^ )

> 
> 
> Hm... I guess I understand now, you need a task parallelization, right?
> 
> In order to do this, you usually separate the task into several independent sub-tasks, put into a queue and wait until it is finished.
> 
> For example, we have a list of files to download from remote server. For each file, we create a new connection and retrieve it independently (and, possibly, out of order):
> 
> import tango.core.ThreadPool;
> 
> void execute()
> {
>     auto pool = new ThreadPool!(string)(10); // create a thread pool with 10 threads
>     string[] fileList = loadFileList();
>     foreach (string filePath; fileList) {
>         pool.append(&download, filePath);   // append the task
>     }
> 
>     pool.finish(); // wait until all the tasks complete
> }
> 
> void download(string fileName)
> {
>     // ...
> }
> 
> In this example, I create a lot of threads (more than hardware runs concurrently) because the CPU is not a bottleneck. You may experience different results in different CPU workaload, though.
> 
> Hope that helps.
> 

On Sat, Jan 10, 2009 at 12:30 AM, Jarrett Billingsley <jarrett.billingsley@gmail.com> wrote:
> On Sat, Jan 10, 2009 at 12:18 AM, yes <yes@no.com> wrote:
>> Does Phobos also do threadpools?
>
> From what I understand, not without modification.  At least, not efficiently.  Downs has implemented such a thing in scrapple.tools, but it requires a patch to Phobos to make it run at a reasonable speed.

Ffffffff.. ignore this, I was thinking about fiber pools.  I don't think there's any technical reason why a ThreadPool couldn't be written for Phobos, but there isn't one provided by default.

On Sat, Jan 10, 2009 at 12:18 AM, yes <yes@no.com> wrote:
> Does Phobos also do threadpools?

From what I understand, not without modification.  At least, not efficiently.  Downs has implemented such a thing in scrapple.tools, but it requires a patch to Phobos to make it run at a reasonable speed.

> Somehow I liked the idea of an Object like agent smith, just duplicate yourself when the task is too big. ( ^_^ )

Hehe.

Jarrett Billingsley wrote:
> On Sat, Jan 10, 2009 at 12:30 AM, Jarrett Billingsley <jarrett.billingsley@gmail.com> wrote:
>> On Sat, Jan 10, 2009 at 12:18 AM, yes <yes@no.com> wrote:
>>> Does Phobos also do threadpools?
>> From what I understand, not without modification.  At least, not efficiently.  Downs has implemented such a thing in scrapple.tools, but it requires a patch to Phobos to make it run at a reasonable speed.
> 
> Ffffffff.. ignore this, I was thinking about fiber pools.  I don't think there's any technical reason why a ThreadPool couldn't be written for Phobos, but there isn't one provided by default.

Scrapple.Tools has a Threadpool too :)

On Sat, Jan 10, 2009 at 6:39 AM, downs <default_357-line@yahoo.de> wrote:
> Jarrett Billingsley wrote:
>> On Sat, Jan 10, 2009 at 12:30 AM, Jarrett Billingsley <jarrett.billingsley@gmail.com> wrote:
>>> On Sat, Jan 10, 2009 at 12:18 AM, yes <yes@no.com> wrote:
>>>> Does Phobos also do threadpools?
>>> From what I understand, not without modification.  At least, not efficiently.  Downs has implemented such a thing in scrapple.tools, but it requires a patch to Phobos to make it run at a reasonable speed.
>>
>> Ffffffff.. ignore this, I was thinking about fiber pools.  I don't think there's any technical reason why a ThreadPool couldn't be written for Phobos, but there isn't one provided by default.
>
> Scrapple.Tools has a Threadpool too :)
>

NO!  *SLAM*