dave's blog

set head off
set lines 200
set feedback off
set define off
spool dbv.sh

select 'dbv file='||name||' blocksize = '||block_size||
       ' LOGFILE=FILE-'||FILE#||'.LOG' from v$datafile;
spool off

host chmod 755 dbv.sh
spool dbv_results.log
host ./dbv.sh
spool off

$ sqlplus "/ as sysdba" @run-dbv.sql

grant select on v_$session to &traceuser.;
grant select on v_$sesstat to &traceuser.;
grant select on v_$statname to &traceuser.;

I came across a situation where the profiler.sql supplied with Metalink Doc: 243755.1 was giving some incomplete results. Because some of my PL/SQL code was executing very quickly it was rounding down to 0.00 and not even showing up on the 'Top 10' section.

Throughout profiler.sql there are timing numbers (unit = sends) that are rounded to 2 places. Looking in the comments for profiler.sql I noticed the last update was early 2007. Maybe Moore's law and CPU power has caught up with profiler.sql but I would recommend increasing the granularity of the script by doing the following:

If you are experimenting with gathering system statistics it might be helpful to archive your current settings and any intermediate settings you come up with along the way.

There is a way to save stats to a table using DBMS_STATS.CREATE_STAT_TABLE and gathering with DBMS_STATS.GATHER into that table, but the format is cryptic and it is nice to have the descriptive parameter names tagging along with the data. (In a future post I will cover format of the CREATE_STAT_TABLE format).

The current system stats info is held in the sys.aux_stats$ table. Since the format is a little wacky, I came up with the following table to hold stats and the following insert statement to populate it after every gathering of system stats.

Now you can easily query the values of old stats in the SYSTEM_STATS_HISTORY table:

#!/usr/bin/bash
#---------------------------------------------------------------------------
# Written by  : David Mann @ http://ba6.us
# Script Name : alldatafiles.sh
# Description : Provides list of all datafiles for each running database on 
#               on a machine
#---------------------------------------------------------------------------

ORATAB=/etc/oratab
echo "INSTANCE_NAME, FILE_NAME"

# Step through running instances
ps -ef | grep ora_smon_ | grep -v grep | cut -b61-70 | while read LINE
do
    # Assign the ORACLE_SID
    ORACLE_SID=$LINE

/usr/ucb/ps
/usr/ucb/ps -auxwww

I ran across Orion in a Kevin Closson blog post. From the OTN site:

"ORION (Oracle I/O Calibration Tool) is a standalone tool for calibrating the I/O performance for storage systems that are intended to be used for Oracle databases. The calibration results are useful for understanding the performance capabilities of a storage system, either to uncover issues that would impact the performance of an Oracle database or to size a new database installation. Since ORION is a standalone tool, the user is not required to create and run an Oracle database. "

SQL> GRANT SELECT ON V_$SESSION TO &&MYUSER;
SQL> GRANT SELECT ON V_$SQL TO &&MYUSER;