Hi,  i have exactly the same problem like here : https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvn17436 (Chassis 2 R0/0: smand: 2/RP/0: Used Memory value 97% ) but running Version 17.3.1 which is meant in "known fixed released"...and as a bonus ant...

I have same issue but with IOS  16.12.3a, which is mentioned in "Known fixes releases".... so on which version should i upgrade?