Queries Generating High "Cell Single Block Physical Read" Wait Messages
Last updated on JANUARY 23, 2018
Applies to:Oracle Database - Enterprise Edition - Version 220.127.116.11 and later
Information in this document applies to any platform.
Symptoms of this issue will appear as follows:
- Trace file entries that look similar to the following:
- The "Top 10 Foreground Events by Total Wait Time" section of the AWR report shows an exceedingly high number of waits but few to no average wait time. For example:
|Event||Waits||Total Wait Time (sec)||Wait Avg(ms)||% DB time||Wait Class|
|cell single block physical read||19,654,319||4847,1||0||9.7||User I/O|
- All or most of the events in the "Top SQL with Top Events" section of the ASH report are INDEX - STORAGE FAST FULL SCAN.
Sign In with your My Oracle Support account
Don't have a My Oracle Support account? Click to get started
My Oracle Support provides customers with access to over a
Million Knowledge Articles and hundreds of Community platforms