int ActiveThreads;
volatile bool AllThreadsShouldExit;
Thread threads[MAX_THREADS];
- Lock MPLock;
+ Lock MPLock, WaitLock;
WaitCondition WaitCond[MAX_THREADS];
};
// Multi-threads related variables
Depth MinimumSplitDepth;
int MaxThreadsPerSplitPoint;
- bool UseSleepingMaster;
ThreadsManager ThreadsMgr;
// Node counters, used only by thread[0] but try to keep in different cache
MaxThreadsPerSplitPoint = Options["Maximum Number of Threads per Split Point"].value<int>();
MultiPV = Options["MultiPV"].value<int>();
UseLogFile = Options["Use Search Log"].value<bool>();
- UseSleepingMaster = Options["Use Sleeping Master"].value<bool>();
if (UseLogFile)
LogFile.open(Options["Search Log Filename"].value<std::string>().c_str(), std::ios::out | std::ios::app);
init_eval(ThreadsMgr.active_threads());
}
+ // Wake up needed threads
+ for (int i = 1; i < newActiveThreads; i++)
+ ThreadsMgr.wake_sleeping_thread(i);
+
// Set thinking time
int myTime = time[pos.side_to_move()];
int myIncrement = increment[pos.side_to_move()];
if (UseLogFile)
LogFile.close();
+ // This makes all the threads to go to sleep
+ ThreadsMgr.set_active_threads(1);
+
return !Quit;
}
<< " time " << current_search_time() << endl;
// Print the best move and the ponder move to the standard output
- if (pv[0] == MOVE_NONE)
+ if (pv[0] == MOVE_NONE || MultiPV > 1)
{
pv[0] = rml.move(0);
pv[1] = MOVE_NONE;
&& !isCheck
&& refinedValue < beta - razor_margin(depth)
&& ttMove == MOVE_NONE
- && (ss-1)->currentMove != MOVE_NULL
&& !value_is_mate(beta)
&& !pos.has_pawn_on_7th(pos.side_to_move()))
{
continue;
}
+
+ // Prune neg. see moves at low depths
+ if ( predictedDepth < 2 * ONE_PLY
+ && bestValue > value_mated_in(PLY_MAX)
+ && pos.see_sign(move) < 0)
+ {
+ if (SpNode)
+ lock_grab(&(sp->lock));
+
+ continue;
+ }
}
// Step 13. Make the move
assert(threadID >= 0 && threadID < MAX_THREADS);
- int i;
- bool allFinished = false;
-
while (true)
{
// Slave threads can exit as soon as AllThreadsShouldExit raises,
// If we are not thinking, wait for a condition to be signaled
// instead of wasting CPU time polling for work.
- while ( threadID >= ActiveThreads
- || threads[threadID].state == THREAD_INITIALIZING
- || (threads[threadID].state == THREAD_AVAILABLE && (!sp || UseSleepingMaster)))
+ while (threadID >= ActiveThreads || threads[threadID].state == THREAD_INITIALIZING)
{
- lock_grab(&MPLock);
-
- // Test with lock held to avoid races with wake_sleeping_thread()
- for (i = 0; sp && i < ActiveThreads && !sp->slaves[i]; i++) {}
- allFinished = (i == ActiveThreads);
-
- // Retest sleep conditions under lock protection
- if ( AllThreadsShouldExit
- || allFinished
- || !( threadID >= ActiveThreads
- || threads[threadID].state == THREAD_INITIALIZING
- || (threads[threadID].state == THREAD_AVAILABLE && (!sp || UseSleepingMaster))))
- {
- lock_release(&MPLock);
+ assert(!sp);
+ assert(threadID != 0);
+
+ if (AllThreadsShouldExit)
break;
- }
- // Put thread to sleep
threads[threadID].state = THREAD_AVAILABLE;
- cond_wait(&WaitCond[threadID], &MPLock);
- lock_release(&MPLock);
+
+ lock_grab(&WaitLock);
+
+ if (threadID >= ActiveThreads || threads[threadID].state == THREAD_INITIALIZING)
+ cond_wait(&WaitCond[threadID], &WaitLock);
+
+ lock_release(&WaitLock);
}
// If this thread has been assigned work, launch a search
assert(threads[threadID].state == THREAD_SEARCHING);
threads[threadID].state = THREAD_AVAILABLE;
-
- // Wake up master thread so to allow it to return from the idle loop in
- // case we are the last slave of the split point.
- if (UseSleepingMaster && threadID != tsp->master && threads[tsp->master].state == THREAD_AVAILABLE)
- wake_sleeping_thread(tsp->master);
}
// If this thread is the master of a split point and all slaves have
// finished their work at this split point, return from the idle loop.
- for (i = 0; sp && i < ActiveThreads && !sp->slaves[i]; i++) {}
- allFinished = (i == ActiveThreads);
+ int i = 0;
+ for ( ; sp && i < ActiveThreads && !sp->slaves[i]; i++) {}
- if (allFinished)
+ if (i == ActiveThreads)
{
// Because sp->slaves[] is reset under lock protection,
// be sure sp->lock has been released before to return.
// Initialize global locks
lock_init(&MPLock);
+ lock_init(&WaitLock);
for (i = 0; i < MAX_THREADS; i++)
cond_init(&WaitCond[i]);
for (int j = 0; j < MAX_ACTIVE_SPLIT_POINTS; j++)
lock_destroy(&(threads[i].splitPoints[j].lock));
+ lock_destroy(&WaitLock);
lock_destroy(&MPLock);
// Now we can safely destroy the wait conditions
// Initialize the split point object
splitPoint.parent = masterThread.splitPoint;
- splitPoint.master = master;
splitPoint.stopRequest = false;
splitPoint.ply = ply;
splitPoint.depth = depth;
assert(i == master || threads[i].state == THREAD_BOOKED);
threads[i].state = THREAD_WORKISWAITING; // This makes the slave to exit from idle_loop()
- if (i != master)
- wake_sleeping_thread(i);
}
// Everything is set up. The master thread enters the idle loop, from
void ThreadsManager::wake_sleeping_thread(int threadID) {
- lock_grab(&MPLock);
+ lock_grab(&WaitLock);
cond_signal(&WaitCond[threadID]);
- lock_release(&MPLock);
+ lock_release(&WaitLock);
}