What is the negative limit value in timing checks?

[psungil]

Hi, all~


When is using negative limit value in $setuphold or $recrem timing system tasks?
what means of negative limit ?

please.

 

[xworld2008]

The negative time is in library or sdf from p&r?
If negative time is in library, you don't care about it. it is becase that some path of the cell is slow, so some time is negative.
The negative is native delay so don't care about it.