I/O issues on DB 11g
- From: David Ramírez Reyes <dramirezr@xxxxxxxxx>
- To: "'oracle-l@xxxxxxxxxxxxx' (oracle-l@xxxxxxxxxxxxx)" <oracle-l@xxxxxxxxxxxxx>
- Date: Wed, 23 Apr 2014 15:39:46 -0500
Hi All,
This is the environment.
Windows 2008 R1 Standard, Oracle DB 11g Standard R2, 8 cpu's, 16 GB of
physical memory, 3 disk drives (1 for the OS, 1 for db files, 1 for
backups).
Now the problem:
Since we went live with the 11g system about 1 year ago (we used to be on a
very old and horrible 8i -don't ask why-), we have been receiving Email
alerts about Disk Utilization; at the beginning I thought it should be a
bug of the R2 version as I wrongly understood it was referring about
filesystem space, which is not a problem.
After several months of 5 or 8 daily mails, I decided to look at it on
detail and check what was necessary to drop off that "false alarm".
After Goggling, I realized that the alarm is not related to disk space, but
I/O reads, as we have 3 db's on the same disk drive, each of them with 20
db files (the biggest DB has datafiles of about 6 GB, the smallest about 2
GB).
The problem is not really "critical" now because general performance is
"good" (we have more than a year with it!), but that of course does not
mean it has to keep on with those problems (and that alarm is starting
causing me headaches also!).
The first two things I though were increasing the PGA size in order to
reduce Virtual Memory usage (and, I/O as consequence) and add 2 more disk
drives to split the db files of each db into a single and dedicated
filesystem; I was also thinking about tuning some high I/O queries, but
don't think the difference could be huge...
Any ideas or suggestions?
Thanks
David Ramírez
Other related posts:
