We're getting inconsistent results running a large fix insert/pack in a very tall cylinder on 32 processors. We have it set up to insert 700,000 particles, but the number we actually get when we run varies widely. On the first run, it generated ~200,000 particles and on a second run it generated ~400,000. (We ran those first two with LIGGGHTS 2.3.6, then we updated to 2.3.8 and ran one more that acted the same and generated ~350,000 particles.)
It seems like some processors aren't inserting their share of the particles, as the results show large sections of the cylinder unfilled. We get the following warning message: "WARNING: Particle insertion: Less insertions than requested (fix_insert.cpp:650)" (it was fix_insert.cpp:648 in 2.3.8)
I took a look at the source code in that spot, but it seems you're just tallying the actual count there to see if there was a problem or not. I couldn't figure out much for myself beyond that.
Here are my STL geometry files and the liggghts input file.