I take it as a simulator control (setting) variable, not
something technology-specific.
There is some chance that this variable simply exists
and is left to default, so nothing setting it explicitly
turns up when you grep the file-pile.
And this in turn might be because all it needs to be is
some sane number that lets the simulator try hard
enough, but not stupid long, before throwing the
"internal timestep too small" flag.
And if that is the case, see post #2.