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 |
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