Simplify and fix job scheduler, especially with respect to the priority system.
[dcpomatic.git] / src / lib / job_manager.cc
index 358820c6a3c35a0ff88d3a295f2c3566435a58e1..608df7ef0af9063729824f7c3967d6d76b7a02fe 100644 (file)
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2012-2020 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2012-2021 Carl Hetherington <cth@carlh.net>
 
     This file is part of DCP-o-matic.
 
 
 */
 
+
 /** @file  src/job_manager.cc
  *  @brief A simple scheduler for jobs.
  */
 
-#include "job_manager.h"
-#include "job.h"
-#include "cross.h"
+
 #include "analyse_audio_job.h"
 #include "analyse_subtitles_job.h"
+#include "cross.h"
 #include "film.h"
+#include "job.h"
+#include "job_manager.h"
 #include <boost/thread.hpp>
-#include <boost/foreach.hpp>
-#include <iostream>
 
-using std::string;
+
+using std::dynamic_pointer_cast;
+using std::function;
 using std::list;
-using std::cout;
+using std::make_shared;
 using std::shared_ptr;
+using std::string;
 using std::weak_ptr;
-using boost::function;
-using std::dynamic_pointer_cast;
-using boost::optional;
 using boost::bind;
+using boost::optional;
+
+
+JobManager* JobManager::_instance = nullptr;
 
-JobManager* JobManager::_instance = 0;
 
 JobManager::JobManager ()
-       : _terminate (false)
-       , _paused (false)
 {
 
 }
 
+
 void
 JobManager::start ()
 {
@@ -60,11 +62,12 @@ JobManager::start ()
 #endif
 }
 
+
 JobManager::~JobManager ()
 {
        boost::this_thread::disable_interruption dis;
 
-       BOOST_FOREACH (boost::signals2::connection& i, _connections) {
+       for (auto& i: _connections) {
                i.disconnect ();
        }
 
@@ -79,6 +82,7 @@ JobManager::~JobManager ()
        } catch (...) {}
 }
 
+
 shared_ptr<Job>
 JobManager::add (shared_ptr<Job> j)
 {
@@ -88,39 +92,42 @@ JobManager::add (shared_ptr<Job> j)
                _empty_condition.notify_all ();
        }
 
-       emit (boost::bind (boost::ref (JobAdded), weak_ptr<Job> (j)));
+       emit (boost::bind(boost::ref(JobAdded), weak_ptr<Job>(j)));
 
        return j;
 }
 
+
 shared_ptr<Job>
 JobManager::add_after (shared_ptr<Job> after, shared_ptr<Job> j)
 {
        {
                boost::mutex::scoped_lock lm (_mutex);
-               list<shared_ptr<Job> >::iterator i = find (_jobs.begin(), _jobs.end(), after);
+               auto i = find (_jobs.begin(), _jobs.end(), after);
                DCPOMATIC_ASSERT (i != _jobs.end());
                _jobs.insert (i, j);
                _empty_condition.notify_all ();
        }
 
-       emit (boost::bind (boost::ref (JobAdded), weak_ptr<Job> (j)));
+       emit (boost::bind(boost::ref(JobAdded), weak_ptr<Job>(j)));
 
        return j;
 }
 
-list<shared_ptr<Job> >
+
+list<shared_ptr<Job>>
 JobManager::get () const
 {
        boost::mutex::scoped_lock lm (_mutex);
        return _jobs;
 }
 
+
 bool
 JobManager::work_to_do () const
 {
        boost::mutex::scoped_lock lm (_mutex);
-       list<shared_ptr<Job> >::const_iterator i = _jobs.begin();
+       auto i = _jobs.begin();
        while (i != _jobs.end() && (*i)->finished()) {
                ++i;
        }
@@ -128,12 +135,13 @@ JobManager::work_to_do () const
        return i != _jobs.end ();
 }
 
+
 bool
 JobManager::errors () const
 {
        boost::mutex::scoped_lock lm (_mutex);
-       BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
-               if (i->finished_in_error ()) {
+       for (auto i: _jobs) {
+               if (i->finished_in_error()) {
                        return true;
                }
        }
@@ -141,65 +149,61 @@ JobManager::errors () const
        return false;
 }
 
+
 void
 JobManager::scheduler ()
 {
+       start_of_thread ("JobManager");
+
        while (true) {
 
                boost::mutex::scoped_lock lm (_mutex);
 
-               while (true) {
-                       bool have_new = false;
-                       bool have_running = false;
-                       BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
-                               if (i->running()) {
-                                       have_running = true;
-                               }
-                               if (i->is_new()) {
-                                       have_new = true;
-                               }
-                       }
-
-                       if ((!have_running && have_new) || _terminate) {
-                               break;
-                       }
-
-                       _empty_condition.wait (lm);
-               }
-
                if (_terminate) {
                        break;
                }
 
-               BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
-                       if (i->is_new()) {
-                               _connections.push_back (i->FinishedImmediate.connect(bind(&JobManager::job_finished, this)));
-                               i->start ();
+               bool have_running = false;
+               for (auto i: _jobs) {
+                       if (have_running && i->running()) {
+                               i->pause_by_priority();
+                       } else if (!have_running && (i->is_new() || i->paused_by_priority())) {
+                               if (i->is_new()) {
+                                       _connections.push_back (i->FinishedImmediate.connect(bind(&JobManager::job_finished, this)));
+                                       i->start ();
+                               } else {
+                                       i->resume ();
+                               }
                                emit (boost::bind (boost::ref (ActiveJobsChanged), _last_active_job, i->json_name()));
                                _last_active_job = i->json_name ();
-                               /* Only start one job at once */
-                               break;
+                               have_running = true;
+                       } else if (!have_running && i->running()) {
+                               have_running = true;
                        }
                }
+
+               _empty_condition.wait (lm);
        }
 }
 
+
 void
 JobManager::job_finished ()
 {
        {
                boost::mutex::scoped_lock lm (_mutex);
-               emit (boost::bind (boost::ref (ActiveJobsChanged), _last_active_job, optional<string>()));
+               emit (boost::bind(boost::ref (ActiveJobsChanged), _last_active_job, optional<string>()));
                _last_active_job = optional<string>();
        }
 
        _empty_condition.notify_all ();
 }
 
+
 JobManager *
 JobManager::instance ()
 {
-       if (_instance == 0) {
+       if (!_instance) {
                _instance = new JobManager ();
                _instance->start ();
        }
@@ -207,13 +211,15 @@ JobManager::instance ()
        return _instance;
 }
 
+
 void
 JobManager::drop ()
 {
        delete _instance;
-       _instance = 0;
+       _instance = nullptr;
 }
 
+
 void
 JobManager::analyse_audio (
        shared_ptr<const Film> film,
@@ -226,8 +232,8 @@ JobManager::analyse_audio (
        {
                boost::mutex::scoped_lock lm (_mutex);
 
-               BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
-                       shared_ptr<AnalyseAudioJob> a = dynamic_pointer_cast<AnalyseAudioJob> (i);
+               for (auto i: _jobs) {
+                       auto a = dynamic_pointer_cast<AnalyseAudioJob> (i);
                        if (a && a->path() == film->audio_analysis_path(playlist) && !i->finished_cancelled()) {
                                i->when_finished (connection, ready);
                                return;
@@ -240,7 +246,7 @@ JobManager::analyse_audio (
        {
                boost::mutex::scoped_lock lm (_mutex);
 
-               job.reset (new AnalyseAudioJob (film, playlist, from_zero));
+               job = make_shared<AnalyseAudioJob> (film, playlist, from_zero);
                connection = job->Finished.connect (ready);
                _jobs.push_back (job);
                _empty_condition.notify_all ();
@@ -261,8 +267,8 @@ JobManager::analyse_subtitles (
        {
                boost::mutex::scoped_lock lm (_mutex);
 
-               BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
-                       shared_ptr<AnalyseSubtitlesJob> a = dynamic_pointer_cast<AnalyseSubtitlesJob> (i);
+               for (auto i: _jobs) {
+                       auto a = dynamic_pointer_cast<AnalyseSubtitlesJob> (i);
                        if (a && a->path() == film->subtitle_analysis_path(content)) {
                                i->when_finished (connection, ready);
                                return;
@@ -275,13 +281,13 @@ JobManager::analyse_subtitles (
        {
                boost::mutex::scoped_lock lm (_mutex);
 
-               job.reset (new AnalyseSubtitlesJob(film, content));
+               job = make_shared<AnalyseSubtitlesJob>(film, content);
                connection = job->Finished.connect (ready);
                _jobs.push_back (job);
                _empty_condition.notify_all ();
        }
 
-       emit (boost::bind (boost::ref (JobAdded), weak_ptr<Job> (job)));
+       emit (boost::bind(boost::ref(JobAdded), weak_ptr<Job>(job)));
 }
 
 
@@ -292,8 +298,8 @@ JobManager::increase_priority (shared_ptr<Job> job)
 
        {
                boost::mutex::scoped_lock lm (_mutex);
-               list<shared_ptr<Job> >::iterator last = _jobs.end ();
-               for (list<shared_ptr<Job> >::iterator i = _jobs.begin(); i != _jobs.end(); ++i) {
+               auto last = _jobs.end ();
+               for (auto i = _jobs.begin(); i != _jobs.end(); ++i) {
                        if (*i == job && last != _jobs.end()) {
                                swap (*i, *last);
                                changed = true;
@@ -304,35 +310,11 @@ JobManager::increase_priority (shared_ptr<Job> job)
        }
 
        if (changed) {
-               priority_changed ();
+               _empty_condition.notify_all ();
+               emit (boost::bind(boost::ref(JobsReordered)));
        }
 }
 
-void
-JobManager::priority_changed ()
-{
-       {
-               boost::mutex::scoped_lock lm (_mutex);
-
-               bool first = true;
-               BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
-                       if (first) {
-                               if (i->is_new ()) {
-                                       i->start ();
-                               } else if (i->paused_by_priority ()) {
-                                       i->resume ();
-                               }
-                               first = false;
-                       } else {
-                               if (i->running ()) {
-                                       i->pause_by_priority ();
-                               }
-                       }
-               }
-       }
-
-       emit (boost::bind (boost::ref (JobsReordered)));
-}
 
 void
 JobManager::decrease_priority (shared_ptr<Job> job)
@@ -341,8 +323,8 @@ JobManager::decrease_priority (shared_ptr<Job> job)
 
        {
                boost::mutex::scoped_lock lm (_mutex);
-               for (list<shared_ptr<Job> >::iterator i = _jobs.begin(); i != _jobs.end(); ++i) {
-                       list<shared_ptr<Job> >::iterator next = i;
+               for (auto i = _jobs.begin(); i != _jobs.end(); ++i) {
+                       auto next = i;
                        ++next;
                        if (*i == job && next != _jobs.end()) {
                                swap (*i, *next);
@@ -353,10 +335,12 @@ JobManager::decrease_priority (shared_ptr<Job> job)
        }
 
        if (changed) {
-               priority_changed ();
+               _empty_condition.notify_all ();
+               emit (boost::bind(boost::ref(JobsReordered)));
        }
 }
 
+
 void
 JobManager::pause ()
 {
@@ -366,7 +350,7 @@ JobManager::pause ()
                return;
        }
 
-       BOOST_FOREACH (shared_ptr<Job> i, _jobs) {
+       for (auto i: _jobs) {
                if (i->pause_by_user()) {
                        _paused_job = i;
                }
@@ -375,6 +359,7 @@ JobManager::pause ()
        _paused = true;
 }
 
+
 void
 JobManager::resume ()
 {