IOS Upgrade Queries

[SR70982]

Hello Experts, 

We have upgraded our ASR 1001-X box from 16.3.3 to 16.12.4 and I observed the below difference when compared 

Below :

memory free low-watermark processor 376517  - This is added in new IOS 16.12.4 and absent in 16.3.3

What could be the reason and is it impacting

username <name> privilege 15 secret 9 - Secret 9 is added in 16.12.4 and its Secret 5 as usual in 16.3.3 Version

Why Secret 9 is added 

Could someone help to clarify this queries  

[balaji.bandi]

memory free low-watermark processor 376517

If above added to config-router to issue notifications when available memory falls below a specified threshold

username <name> privilege 15 secret 9 

Due to security, moving forward is type 9 - you can read the release notes this is expected.

Username secret password type 5 and enable secret password type 5 must be migrated to the stronger password type 8 or 9.