We have a small functionality change in case we have a
fail-high so that both rml[].pv and pv[] are updated, but if,
after researching, we have a fail-low then rml score is updated
again but pv[] remains the same and coming back from search we
used a PV line that has failed-low (after having failed-high).
With this patch we always use the 'correct' PV line, i.e. the
line with highest score at the end of the whole search.
Retire also redundant RootMove's 'move' member and directly
use pv[0] instead.
When a reference breaks things !
Here we take a reference (that is a pointer) to an
entry in a vector that changes below us --> BOOM !
References are essential but should be considered with
care in C++ because could lead to nasty surprises.
Restored functionality.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Instead of a default member by member copy use set_pv()
to copy the useful part of pv[] array and skip the remaining.
This greatly speeds up sorting of root move list !
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
It is redundant being a move list ;-)
Also better document the two scores used by root list.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Namely we use only two types of depth in TT:
DEPTH_QS_CHECKS or DEPTH_QS_NO_CHECKS.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Use one sleep lock per thread insted of a single one shared.
Also renamed WaitLock in SleepLock.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
By mean of an an UCI option it is possible let the available
threads to sleep, this should help with Hyper Threading although
is not the best solution when number of threads equals number
of available cores.
Option is disabled by default.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Non-PV LMR is left unchanged.
After 8819 games
Mod- Orig: 1442 - 1343 - 6034 ELO +3 (+- 2.9) LOS 86%
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
After 2036 games Mod- Orig:
381 - 278 - 1377 ELO +17 (+- 6.2) LOS 99%
One of the biggest increases ever !
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
When MultiPV > 1, always take bestmove from the RootMoveList
(and don't bother with a ponder move). Without that the bestmove
is most probably incorrect.
Patch from Peter Petrov.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
It is a redundant boiler plate, just call initialization and
resource release directly from main()
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Let to sleep even split point master, it will be waken
up by its slaves when they return from the search.
This time let it be enabled by an UCI option, so
people is free to test it on their Hyper Thread box.
Option is disabled by default.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
I finally got SF to compile under MinGW (after adding pthread libraries)
and here are the fixed warnings.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
And also store the node counter in Position and not in Thread.
This will allow to properly count nodes also in sub trees with
SMP active.
This requires a surprisingly high number of changes
in a lot of places to make it work properly.
No functional change but node count changed for obvious reasons.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This was subtle and google was my friend.
The leak was in _dl_allocate_tls called by pthread_create() and
is due to the fact that threads are created in joinable state so that
once terminated are not freed. To make the thread to release
its resources upon termination we should set them in detached state.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
It seems we have a speed regression under Linux, anyhow
commit and revert to leave some documentation in case we
want to try again in the future.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Let to sleep even split point master, it will be waken up
by its slaves when they return from the search.
With this patch we get maximum HT speedup
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
It has more sense to treat the two evaluation metrics
in the same way.
As a side effect now we use the correct eval margin when
pruning in a SplitPoint node.
No functional change in single thread.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
Fix the movcount updating bug and let search() to completely
subsititute sp_search().
No functional change even with fakes split.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
There is a bug in the conversion that is triggered when testing
with faked split and that I missed somehow :-(
To allow proper testing on cluster restore old sp_search()
until I don't fiugre up what's happened.
Restored to be functional equivalent to old behaviour both in
single thread and in faked split.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
When entering and exiting from think() we don't need any special
wake up / sleeping code because we want available threads to keep
sleeping.
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This simple patch has devastating consequences ;-)
Now an available thread goes to sleep and is waked up after
being allocated.
This patch allows Stockfish to dramatically increase performances
on HyperThreading systems.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
They are fast and also have the same semantic of Linux ones.
This allow to simplify the code and especially to use
SleepConditionVariableSRW() to wait on a condition releaseing the lock,
this has the same semantic as pthread_cond_wait().
No functional change.
Signed-off-by: Marco Costalba <mcostalba@gmail.com>
