listStatus should update files' lastSyncTime under the directory for HDFS

Is your feature request related to a problem? Please describe.

When ufs is hdfs, listStatus a directory

1. syncs and updates meta data of files under it
2. does not updates lastSyncTime of files under it

These causes accessing a file under the directory just after listStatus needs to sync meta once more.

Below is an example with alluxio.user.file.metadata.sync.interval=5m

// 1. the meta data of the file is outdated
$ bin/alluxio fs ls -Dalluxio.user.file.metadata.sync.interval=-1 /nginx/master.log
-rw-rw-r--  alluxio   alluxio   2036694       PERSISTED 04-29-2022 12:18:00:414 100% /nginx/master.log

// 2. listStatus on the directory
$ bin/alluxio fs ls /nginx
-rw-rw-r--  alluxio   alluxio   2037635       PERSISTED 04-29-2022 12:22:22:016   0% /nginx/master.log

// 3. check audit log at hdfs side
$ tail hdfs-audit.log|grep nginx
2022-04-29 12:26:50,818 INFO FSNamesystem.audit: allowed=true   ugi=... ip=... cmd=getfileinfo src=.../nginx
2022-04-29 12:26:50,821 INFO FSNamesystem.audit: allowed=true   ugi=... ip=... cmd=listStatus  src=.../nginx

// 4. check meta data of the file at alluxio side, it is updated
$ bin/alluxio fs ls -Dalluxio.user.file.metadata.sync.interval=-1 /nginx/master.log
-rw-rw-r--  alluxio   alluxio   2037635       PERSISTED 04-29-2022 12:22:22:016   0% /nginx/master.log

// 5. access the file with normal style
$ bin/alluxio fs ls /nginx/master.log
-rw-rw-r--  alluxio  alluxio    2037635       PERSISTED 04-29-2022 12:22:22:016   0% /nginx/master.log

// 6. check audit log at hdfs side, find the meta data of the file synced once more
$ tail hdfs-audit.log|grep nginx
2022-04-29 12:27:06,947 INFO FSNamesystem.audit: allowed=true   ugi=... ip=..  cmd=getfileinfo src=.../nginx/master.log

Describe the solution you’d like listStatus should also update lastSyncTime of files under the directory.

Describe alternatives you’ve considered No

Urgency This can improve the performance of AlluxioMaster.

Additional context Testing based on alluxio-2.7.1

[secfree]

@jiacheliu3 May I know

1. Why is SyncTime.mLastRecursiveSyncMs needed besides SyncTime.mLastSyncMs?
2. Is it ok to update mLastRecursiveSyncMs of the first level children after listStatus the directory without “recursive” option?

Checked the code and learned that I had misunderstanding about updating mLastRecursiveSyncMs. Setting mLastRecursiveSyncMs of the directory is faster than updating all its offsprings, so it is needed.

Please ignore the above two questions here. Sorry for the inconvenience.

[secfree]

#16081 updates the metadata of children if listStatus the directory prefetched the metadata, so I will close this issue.