Myracle GUI

[Mark 1]

Thank you very much for the new update.

[vencenda]

Thank you for the update.

I'm running a tournament, and I have an issue that has happened 3 out of 4 times so far:
If I leave the PC open and leave, letting the tournament run, when I return after a few minutes or hours, I find a message saying "failed to start engine..." and the tournament is paused. Games that are already running finish normally, I believe. It's when a new game is about to start that the issue appears.

It hasn't happened so far while I use the PC, it's always when I leave. I have Windows 11. The PC (it's a laptop) never sleeps or hibernates, but the screen turns off after a few minutes of user inactivity. I don't know if that's the reason, but it didn't happen with Arena or other types of programs. They just keep running with the screen off.

[mar]

I'm running a tournament, and I have an issue that has happened 3 out of 4 times so far:
If I leave the PC open and leave, letting the tournament run, when I return after a few minutes or hours, I find a message saying "failed to start engine..." and the tournament is paused. Games that are already running finish normally, I believe. It's when a new game is about to start that the issue appears.

It hasn't happened so far while I use the PC, it's always when I leave. I have Windows 11. The PC (it's a laptop) never sleeps or hibernates, but the screen turns off after a few minutes of user inactivity. I don't know if that's the reason, but it didn't happen with Arena or other types of programs. They just keep running with the screen off.

just tried to enable screensaver and the test tour I was running continued normally without any problems (tc: 8"+0.08"),
just by chance is it the same engine(s) that fails to start? might be misconfigured in theory,
but then it would happen always, not 3 times out of 4

I give the engines 10 seconds to respond (for UCI engines that means responding to isready after they receive uci),
if they fail to do so I consider it a "load failure"

in theory this could also be caused by using more cores than the GUI can handle without problems
or by some background processes running (even sw updates) or even the OS throttling the CPU
out of curiosity - if you uncheck concurrency when starting a new tour, does the problem persist? also what is your concurrency settings?

also - do you run the engines locally or from say a shared network drive/cloud?

if it's something else then it's a GUI bug that needs fixing - but I can't fix what I can't reproduce

[Andres Valverde]

Thank you for the update.

I'm running a tournament, and I have an issue that has happened 3 out of 4 times so far:
If I leave the PC open and leave, letting the tournament run, when I return after a few minutes or hours, I find a message saying "failed to start engine..." and the tournament is paused. Games that are already running finish normally, I believe. It's when a new game is about to start that the issue appears.

It hasn't happened so far while I use the PC, it's always when I leave. I have Windows 11. The PC (it's a laptop) never sleeps or hibernates, but the screen turns off after a few minutes of user inactivity. I don't know if that's the reason, but it didn't happen with Arena or other types of programs. They just keep running with the screen off.

Does it happens always with the same engine? if so, which one is it ?

[vencenda]

I'm not sure if it was the same engine. I use two versions of Stockfish (18 and dev-20260519-133731f3) and 3 other engines. From what I remember, at least 2 out of 3 times (I think actually all 3 times), it was Stockfish, but I don't remember if it was the same version.

I'll try disabling concurrency, but because of the nature of the issue, I'll need some time before I report back. I use a core budget of 2, and each engine uses one core, so two games are running at the same time. My pc has 10 cores (2P+8E cores) and 12 threads. I run the engines locally.

Now that I'm looking at the games' times, it seems that one of the 3 times, it happened an hour after I left the PC. So maybe it's not related to the screen turning off, and it was just a coincidence.

EDIT: I found an "app.log" file from a backup, and it seems that one of the times it was Stockfish 18. I'll notice if it's the same engine if it happens again.

[vencenda]

(Sorry, unable to edit the previous post again.)

I just found another "app.log" file, and this one was with Stockfish dev-20260519-133731f3.

[mar]

ok thanks, still strange.

I played a minitour with SF18 here and no problems.
can I ask about the setup? specifically syzygy, hash size and so on
the engine has to start up within 10 seconds, including allocating and clearing hashtable and initializing syzygy
I always thought that should be more than generous (unless there's some other problem of course)

SF18 startup time here is typically around 600ms, that's with 6 man syzygy on an SSD and 256M hash
alternatively along with disabling concurrency you could enable log and then compress and upload the corresponding .debug file,
assuming it happens again? this or alternatively if you go set the combo to strings and locate "engine init took nnn msec"
would be interesting to see how long it typically takes your stockfishes to start up

[mar]

hmm I think I got a repro! - but it only happened once...

if I set hash to very large values, e.g. 32GB for SF it takes around 3.5 seconds to start up here
so maybe 10seconds is not enough in such cases. Myracle doesn't support reuse anyway, so allocating and zero filling
such large amounts of memory can take very long. I may need to increase the limit to larger values or make it configurable
somewhere. I'm thinking perhaps up to 1 minute instead of 10 seconds... but anything above that seems silly...

[vencenda]

I have the tournament running right now and just now Reckless lost two times on time and a couple of games later Stockfish 18 failed to start (this time while I'm at the PC). So far, about 840 games have been played, and this "time forfeit" thing happened for the first time. I'd say that it's my PC's issue, but since it never happened with Arena, I thought that it could have to do with the GUI. I'm using my PC while the tournament is running, but I'm not doing anything heavy.

I'm using 1 thread per engine, 128 mb Hash, time control 30+0.3, no syzygy, no ponder, concurrency of 2. I'm not changing any engines settings other than overriding Hash and Threads.

Here are some info about init times from a few games:
engine init (Stockfish 18) took 2424 msec
engine init (PlentyChess 7.0.0) took 123 msec
engine init (Stockfish 18) took 2212 msec
engine init (Obsidian 16.0) took 814 msec
engine init (Reckless 0.9.0) took 90 msec
engine init (Stockfish dev-20260519-133731f3) took 2047 msec
engine init (Obsidian 16.0) took 190 msec
engine init (PlentyChess 7.0.0) took 108 msec
engine init (Stockfish 18) took 555 msec
engine init (Stockfish dev-20260519-133731f3) took 1964 msec

[mar]

I have the tournament running right now and just now Reckless lost two times on time and a couple of games later Stockfish 18 failed to start (this time while I'm at the PC). So far, about 840 games have been played, and this "time forfeit" thing happened for the first time. I'd say that it's my PC's issue, but since it never happened with Arena, I thought that it could have to do with the GUI. I'm using my PC while the tournament is running, but I'm not doing anything heavy.

I'm using 1 thread per engine, 128 mb Hash, time control 30+0.3, no syzygy, no ponder, concurrency of 2. I'm not changing any engines settings other than overriding Hash and Threads.

Here are some info about init times from a few games:
engine init (Stockfish 18) took 2424 msec
engine init (PlentyChess 7.0.0) took 123 msec
engine init (Stockfish 18) took 2212 msec
engine init (Obsidian 16.0) took 814 msec
engine init (Reckless 0.9.0) took 90 msec
engine init (Stockfish dev-20260519-133731f3) took 2047 msec
engine init (Obsidian 16.0) took 190 msec
engine init (PlentyChess 7.0.0) took 108 msec
engine init (Stockfish 18) took 555 msec
engine init (Stockfish dev-20260519-133731f3) took 1964 msec

ok thanks, could you please upload (ideally compressed) <tourname>.anomaly.log in tournaments subfolder?
this looks like the engine wasn't getting the resources for a while and it's quite suspicious to me

concurrency of 2 on your hw should be very generous, so I wonder why this is happening. also the SF init of >2 seconds with a 128M hash
seems quite long. what's strange that sometimes it's only half a second - are you sure SF is configured to only use 128M?

I'll definitely increase engine startup limit from 10 seconds in the next build. 1 minute seems silly, so I'll probably go with 30 seconds instead or make it configurable. auto-detect limit will be kept at 10secs

btw Arena doesn't run multiple games in parallel, but concurrency of 2 isn't much

is it possible that some heavy processes (utilizing lots of CPU/RAM) were coincidentally running at the same time this happened?