Author Archives: Bobby

Today I was trying to see if upgrading from 11.2.0.2 to 11.2.0.4 would change the SYS.WRH$_SQL_PLAN table.  This table is large on our production system so I wanted to find out if some time-consuming update to this table would occur … Continue reading →

The Unix utilities ps and top report memory differently with HugePages than without. Without HugePages ps -eF seems to include the SGA memory under the SZ column: UID        PID  PPID  C    SZ   RSS PSR STIME TTY          TIME CMD … oracle    … Continue reading →

On Monday we had some performance problems on a system that includes a database which uses shared servers.  The top wait was “virtual circuit wait”.  Here are the top 5 events for a 52 minute time frame: Top 5 Timed … Continue reading →

Just got the invitation to the first AZORA (Arizona Oracle user group) meeting on October 23.  Here is the link: url It’s 2 pm at Oracle’s office, 2355 E Camelback Rd Ste 950, Phoenix, AZ. I’m looking forward to it! … Continue reading →

I have an example of paging in some Exadata OS Watcher log files.  We got an error in the alert log about a high load but reviewing AWR reports it did not seem like we had an unusual number of … Continue reading →

Yesterday and today I’ve read or heard two people mention the force_match => TRUE parameter value for DBMS_SQLTUNE.IMPORT_SQL_PROFILE and how it forces a profile to work on all SQL statements that are the same except for their literal values.  So, … Continue reading →

I saw this fun blog post about the Arizona Oracle User Group getting organized: blog post(updated with meetup page). I’m definitely interested in being involved.  Please pass this on to any Oracle DBAs, developers, etc. that you know in the … Continue reading →

This graph represents commit time compared to CPU utilization and redo log write time.  I’ve included only the hourly intervals with more than 1,000,000 commits.  At these peaks the number of commits ranges 1 to 1.6 million commits per hour … Continue reading →

I am learning about how well commits scale on Oracle 11.2 and so far they seem to scale surprisingly well. I’ve looked at two waits – log file parallel write and log file sync.  Based on documents I’ve read on … Continue reading →

Well, I finally passed the Oracle Certified Professional (OCP) 12c upgrade exam, 1Z0-060.  I got 86% right on the new features section and 78% correct on the general DBA section.  So, that means I missed roughly 7 questions on each … Continue reading →