来源于：
Create or Truncate Table Slow in 12c While Waiting for DFS Lock Handle wait (文档 ID 2085308.1)
APPLIES TO:
Oracle Database - Enterprise Edition - Version 12.1.0.2 and later
Information in this document applies to any platform.
SYMPTOMS
In 12c database, create or truncate table is very slow. High "DFS lock handle" waits are observed. Same create or truncate statement runs faster in 11g.
CHANGES
Upgraded to 12c
CAUSE
The issue is due to inmemory stats being flushed during the truncate of the parent segment.
This has been discussed in below bugs:
Bug 20858716 - CREATE TABLE VERY SLOW
closed as duplicate of
Bug 20171986 - SLOW TRUNCATE ON 12.1.0.2 DUE TO "DFS LOCK HANDLE"
SOLUTION
Download and apply interim patch 20171986 .
REFERENCES
BUG:20858716 - CREATE TABLE VERY SLOW
NOTE:1597161.1 - ORA-00600 Upon 'alter Table [name] No Row Archival'
