experiencing Lag in Arena, AMD 3900X build

[toliveanddie76]

Hello all,
I'll get right to the point as this is my first post. long time chess engine hobbyist. I use Arena chess 3.5.1. I currently have a AMD Ryzen 9 3900X build on a x570 motherboard... yada yada. I can give all specs if needed...

here is what is happening.

Turn on computer
start Arena... create new tournament... pick two engines (each having a book)... start tournament... and for those who use Arena chess know that the book moves are literally moved out instantaneously after the engines start up. in other words, there is no perceptible time gap (lag) in between the very fast book moves being displayed.

this is what I am experiencing.

after I have ran a tournament for maybe 2 to 3 hours, I notice that the book moves aren't being moved out instantaneously.
instead,
each book move now has a perceptible time gap between moves. so instead of an almost instantaneous zip on the moves, they are now paused for a brief split second. almost like there is some background tick that needs to finish, no other way I can explain it. This time gap now also proceeds to affect the match, giving each move a very noticeable gap to when the engine starts to think.
1... restarting Arena does not help.
2... reinstalling Arena does not help (leads me to believe that this is a general system lag)
3... changing hash, and other parameters has not helped (haven't tried them all)
4... changing tournament time parameters hasn't helped.

the only thing that helps is an entire system reboot.

anyone else experiencing this? I have no idea how to start troubleshooting this.

[D Sceviour]

My intuition tells me this is a memory problem. Open the task manager and check memory allocations after "2 or 3 hours" as you claim. The problem may not be attached to the AMD board, but rather to a new engine you are using.

[toliveanddie76]

My intuition tells me this is a memory problem. Open the task manager and check memory allocations after "2 or 3 hours" as you claim. The problem may not be attached to the AMD board, but rather to a new engine you are using.

will do. just know that swapping engines in and out of these tournaments does not change this incremental lag that I am experiencing. its funny, the reason I noticed it was because I had left a tournament running accidentally for over 4 hours! that is when I noticed the book moves being played at this really really slow move rate. it was close to a second between book moves. book moves that are normally raced out almost simultaneously on the board in Arena Chess.

[MikeB]

My intuition tells me this is a memory problem. Open the task manager and check memory allocations after "2 or 3 hours" as you claim. The problem may not be attached to the AMD board, but rather to a new engine you are using.

will do. just know that swapping engines in and out of these tournaments does not change this incremental lag that I am experiencing. its funny, the reason I noticed it was because I had left a tournament running accidentally for over 4 hours! that is when I noticed the book moves being played at this really really slow move rate. it was close to a second between book moves. book moves that are normally raced out almost simultaneously on the board in Arena Chess.

It does appear to be a classic memory issue - what is the hash size, how many concurrent games are you running and what is your total memory?

I'm assuming you are on Windows - when this happens you might want to open 'Task Manager" and check the memory pressure. Windows will use a pagefile (swap to disk) even before you run out of memory , it is designed that way.

The general rule of thumb is to use no more than 50% of you RAM for hash. If you have an engine vs engine match with 16Gb ram , set hash to 4 GB of RAM. If you are running 16 concurrent games on a 16 Core CPU, with 32 GB of RAM , your max hash size per engine should be 512 MB ( 32 engines * 512 MB = 16 Gb).

[Modern Times]

Caching of 6-men Syzygy tablebases can also cause memory issues when running long time controls and a few cores as I found out. I have 16GB of RAM which I thought was plenty but definitely isn't these days. I stick to 5-men now.

[toliveanddie76]

update on this: no more lag.
the lag in Arena, which was very pronounced, did indeed extend to other software. took the computer apart, unplugging the motherboard cmos battery, unplugging the hard drive, formatted the drive, letting all the components sit without power for an hour.
then putting it all back together with a clean installation of windows. whew.

Finally not noticing a tick/lag/pause in the system.

Really very interesting to me that opening book moves being made slower is what opened my eyes to a problem.

time will tell if this pops up again.