【Oracle Database 12c新特性】wait event DISPLAY_NAME

在Oracle database 12c 中引入V$EVENT_NAME 视图新增字段DISPLAY_NAME,该字段用以更详细地解释对应的等待事件:

 

DISPLAY_NAME VARCHAR2(64) A clearer and more descriptive name for the wait event that appears in the NAME column. Names that appear in the DISPLAY_NAME column can change across Oracle Database releases, therefore customer scripts should not rely on names that appear in theDISPLAY_NAME column across releases.

 

可惜的是目前并非所有的event都有对应的DISPLAY_NAME,我们列出在12.1.0.1中现有的display name:

 

select name,display_name,wait_class from v$event_name  where name!=display_name order by name

 

NAME DISPLAY_NAME WAIT_CLASS
DFS db file lock quiesce for datafile offline Other
Image redo gen delay redo resource management Other
LGWR real time apply sync standby apply advance notification Idle
concurrent I/O completion online move datafile IO completion Administrative
control file sequential read control file read System I/O
control file single write control file write System I/O
datafile copy range completion online move datafile copy range completion Administrative
datafile move cleanup during resize online move datafile resize cleanup Other
db file parallel read db list of blocks read User I/O
db file parallel write db list of blocks write System I/O
db file scattered read db multiblock read User I/O
db file sequential read db single block read User I/O
db file single write db single block write User I/O
log buffer space log buffer full – LGWR bottleneck Configuration
log file parallel write log file redo write System I/O
log file sequential read log file multiblock read System I/O
log file single write log file header write System I/O
log file sync commit: log file sync Commit
wait for possible quiesce finish quiesce database completion Administrative