DiskSpace quota exception on hive

[#1]

I am getting error when trying to execute query like this insert into A select * from B;

Caused by: org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.hdfs.protocol.DSQuotaExceededException): The DiskSpace quota of /user/hive/warehouse/adhoc.db is exceeded: quota = 3298534883328 B = 3 TB but diskspace consumed = 3298593288972 B = 3.00 TB

I have enough space on my schema(~2.3TB).The table I am trying to insert is around 800 GB.

Still I am getting the above error.Any reasons

[#2]

This may be due to HDFS default replication set to 3. So the total space requirement would be 800GB * 3 = 2.4TB which exceeds 2.3TB that's available.