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reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
I tried to eliminate the static shared ~this as follows:

https://github.com/dlang/phobos/pull/5470/commits/a4b2323f035b663727349d390719509d0e3247ba

However, unittesting fails at src/core/thread.d(2042). I suspect it's 
because the atexit call occurs too late, after the shared static this in 
src/core/thread.d has already been called.

Thoughts on how to make this work?


Thanks,

Andrei
Jun 11 2017
next sibling parent reply Stanislav Blinov <stanislav.blinov gmail.com> writes:
On Sunday, 11 June 2017 at 19:06:48 UTC, Andrei Alexandrescu 
wrote:

 I tried to eliminate the static shared ~this as follows:

 https://github.com/dlang/phobos/pull/5470/commits/a4b2323f035b663727349d390719509d0e3247ba

 However, unittesting fails at src/core/thread.d(2042). I 
 suspect it's because the atexit call occurs too late, after the 
 shared static this in src/core/thread.d has already been called.

 Thoughts on how to make this work?


 Thanks,

 Andrei


Which atexit call? The shared static ~this is still present in 
that commit.
Jun 11 2017
parent reply Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
On 06/12/2017 12:13 AM, Stanislav Blinov wrote:

 On Sunday, 11 June 2017 at 19:06:48 UTC, Andrei Alexandrescu wrote:

 I tried to eliminate the static shared ~this as follows:

 https://github.com/dlang/phobos/pull/5470/commits/a4b2323f035b66372734
d390719509d0e3247ba 


 However, unittesting fails at src/core/thread.d(2042). I suspect it's 
 because the atexit call occurs too late, after the shared static this 
 in src/core/thread.d has already been called.

 Thoughts on how to make this work?


 Thanks,

 Andrei


 
 Which atexit call? The shared static ~this is still present in that commit.


Eh, the link doesn't work anymore; I hoped it would be immutable. 
Anyhow, I just tried this again:

private final class ParallelismThread : Thread
{
     this(void delegate() dg)
     {
         super(dg);
         static shared bool once;
         import std.concurrency;
         initOnce!once({
             import core.stdc.stdlib;
             atexit(&doThisAtExit);
             return true;
         }());
     }

     TaskPool pool;
}

// Kill daemon threads.
//shared static ~this()
extern(C) void doThisAtExit()
{
     foreach (ref thread; Thread)
     {
         auto pthread = cast(ParallelismThread) thread;
         if (pthread is null) continue;
         auto pool = pthread.pool;
         if (!pool.isDaemon) continue;
         pool.stop();
         pthread.join();
     }
}

There's no more shared static ~this(). Instead, we have an atexit 
registration. It fails in src/core/thread.d(2042).


Andrei
Jun 12 2017
next sibling parent reply Stanislav Blinov <stanislav.blinov gmail.com> writes:
On Monday, 12 June 2017 at 14:21:29 UTC, Andrei Alexandrescu 
wrote:

 On 06/12/2017 12:13 AM, Stanislav Blinov wrote:

 On Sunday, 11 June 2017 at 19:06:48 UTC, Andrei Alexandrescu 
 wrote:

 I tried to eliminate the static shared ~this as follows:

 https://github.com/dlang/phobos/pull/5470/commits/a4b2323f035b663727349d390719509d0e3247ba


 However, unittesting fails at src/core/thread.d(2042). I 
 suspect it's because the atexit call occurs too late, after 
 the shared static this in src/core/thread.d has already been 
 called.

 Thoughts on how to make this work?


 Thanks,

 Andrei


 
 Which atexit call? The shared static ~this is still present in 
 that commit.


 Eh, the link doesn't work anymore; I hoped it would be 
 immutable. Anyhow, I just tried this again:

 private final class ParallelismThread : Thread
 {
     this(void delegate() dg)
     {
         super(dg);
         static shared bool once;
         import std.concurrency;
         initOnce!once({
             import core.stdc.stdlib;
             atexit(&doThisAtExit);
             return true;
         }());
     }

     TaskPool pool;
 }

 // Kill daemon threads.
 //shared static ~this()
 extern(C) void doThisAtExit()
 {
     foreach (ref thread; Thread)
     {
         auto pthread = cast(ParallelismThread) thread;
         if (pthread is null) continue;
         auto pool = pthread.pool;
         if (!pool.isDaemon) continue;
         pool.stop();
         pthread.join();
     }
 }

 There's no more shared static ~this(). Instead, we have an 
 atexit registration. It fails in src/core/thread.d(2042).


 Andrei


To me, it feels like the options are:
1. Take a performance hit and unregister "parallel" threads from 
the runtime at creation, and keep a separate lock-protected list.
2. Modify runtime to allow creating unregistered Threads
3. Push thread_term() call back if at all possible (i.e. by also 
registering it with atexit).

I'll put the PR for (1) up for discussion a bit later. (2) and 
(3) I'll need to dig into runtime somewhat first.
Jun 12 2017
parent Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:
On 06/12/2017 01:43 PM, Stanislav Blinov wrote:

 
 I'll put the PR for (1) up for discussion a bit later. (2) and (3) I'll 
 need to dig into runtime somewhat first.


Thanks! -- Andrei
Jun 12 2017
prev sibling parent Vladimir Panteleev <thecybershadow.lists gmail.com> writes:
On Monday, 12 June 2017 at 14:21:29 UTC, Andrei Alexandrescu 
wrote:

 On 06/12/2017 12:13 AM, Stanislav Blinov wrote:

 On Sunday, 11 June 2017 at 19:06:48 UTC, Andrei Alexandrescu 
 wrote:

 https://github.com/dlang/phobos/pull/5470/commits/a4b2323f035b663727349d390719509d0e3247ba




 Eh, the link doesn't work anymore; I hoped it would be 
 immutable.


https://github.com/andralex/phobos/commit/a4b2323f035b663727349d390719509d0e3247ba
Jun 12 2017
prev sibling parent Moritz Maxeiner <moritz ucworks.org> writes:
On Sunday, 11 June 2017 at 19:06:48 UTC, Andrei Alexandrescu 
wrote:

 I tried to eliminate the static shared ~this as follows:

 https://github.com/dlang/phobos/pull/5470/commits/a4b2323f035b663727349d390719509d0e3247ba

 However, unittesting fails at src/core/thread.d(2042). I 
 suspect it's because the atexit call occurs too late, after the 
 shared static this in src/core/thread.d has already been called.

 Thoughts on how to make this work?


Obligatory reminder that the static shared ~this you are trying 
to port is buggy[1] and any of std.parallelism's alleged "daemon" 
threads being busy in reality keeps the program from terminating.

[1] https://issues.dlang.org/show_bug.cgi?id=16324
Jun 12 2017