Beginners help with latency error / loosing steps

Hey People,

Im new to LinuxCNC, an while I've been digging into it for a few weeks and getting quite far on my own, now im stuck - And would love some professional eyes on my case.

I bought a pre-bulit 3 axis from a hobbyist a while ago. Machine is wonderfully configured, very sound construction. Software... well, i don't know.
Now after some minor adjustments and finally (!) getting my tool probe working properly, i have had two occurrences of loosing steps on Y axis, which is moving the heavy gantry. Simultaneously, i always get a latency warning on startup ("RTAPI: ERROR: Unexpected real time delay on task 1"). Wich also manifests itself in a short freeze of the PC when loading larger gcodes (10 mb and up). At least i guess those issues might be connected - Im a little out of my depth here.
Im running of an old Dell Optiplex 960, sporting a E8000 Processor. I did all the BIOs settings as recommended. So what else could i do? Stepper tuning? (Is that even related to latency issues?) Any ideas?

Looking forward to your help!

All the very best,

Raph.

Parallel port ? Or Mesa ?
If parallel, edit the ini file found in the machine configuration folder and set the Base_period higher, test several times till you get no more warnings.
Beware that that will limit the velocity and might cause joint errors, so the joint/axis velocities will have to be lowered for each axis.

Im on Parallel port.
As a bloody beginner Im hesitant to change any values without knowing what they actually do. Im still reading the manual and sereral posts, and lets just say: it's not a concept that comes naturally to me.
I did a few latency tests, usually around 16000, highest ever recorded was 18000.
The BASE_PERIOD is set to 16666, MAX_VELOCITY set to 140. Does that look about right?

-Try base period at 50000,
-test for at least 1 hour of air cutting, copy files, watch youtube, etc
-if no latency warning, set to 45000
-rinse and repeat.
If you do get warnings at 50000, try 55000 and up, in 5K increments.

Run the latency test, what are the results? (Some things to check, dead/weak CMOS batteries can cause the BIOS to be reset to default settings that might wreck latency where it had been good, also dying hardware (such as a failing HD) can also cause latency problems.)

What is the current base thread speed? (Will need to be some amount less than your worst case latency.)

What is the current step scale, max velocity, max acceleration, and step timing? (All of the scale and speed info is in the ini file.)

Alright, thats something i can work with. Thank you so much!
But would a change of base period in that range affect any other settings that id have to adjust? Just to be sure...