HDFS Sync related metrics:

Histogram for time taken for Sentry end point to process path updates from HMS:
org.apache.sentry.hdfs.SentryHDFSServiceProcessor.handle-hms-notification

Histogram for time taken for Sentry to serve NN requests for updates:
org.apache.sentry.hdfs.SentryHDFSServiceProcessor.get-all-authz-updates-from

Histogram for time taken for HMS to send an update to Sentry:
org.apache.sentry.hdfs.MetastorePlugin.notify-sentry-HMS-update

Histogram for time taken for HMS to apply the path update locally:
org.apache.sentry.hdfs.MetastorePlugin.apply-local-update

Count of path updates in Sentry:(Need to check if this handled compacted numbers as well)
org.apache.sentry.hdfs.SentryHDFSServiceProcessor.paths-updates-size
org.apache.sentry.hdfs.SentryHDFSServiceProcessor.handle-hms-notification.path-changes-size

Histogram:
org.apache.sentry.hdfs.MetastorePlugin.apply-local-update.path-change-size

Error counters:
"org.apache.sentry.hdfs.MetastorePlugin.notify-sentry-HMS-update.failed-num"
"org.apache.sentry.hdfs.SentryHDFSServiceProcessor.handle-hms-notification.failed-num"

"org.apache.sentry.hdfs.SentryHDFSServiceProcessor.handle-hms-notification.has-full-image-num"

Various memory metrics (TODO)