Making LLAP as a first-class YARN service also enables us to use some of the other powerful features in YARN that were added in Apache Hadoop 3.0 / 3.1, some of them are noted below.
Advanced container placement scheduling such as affinity and anti-affinity. What Slider used to handle in a custom way is now a core first-class feature (YARN-6592).
New and improved Services UI in YARN UI2 improving debuggability and log access.
Continuous rolling log aggregation of long running containers (YARN-2443).
Auto-restart of containers by NodeManagers (YARN-4725).
Windowing and threshold based container health monitor (YARN-8122).
Looks like it’s been a fruitful transition.