Performance Tuning :: AWR Report In 11g Standard Not Supported?
Jan 15, 2011
I was trying to generate AWR report, but the report which got generated consist most of the sections without data. Later i came to know that AWR report is not fully supported in 11g? Is that true?
How many records could I have in a single table without performance degradation with Standard Edition without partitioning with cutting-edge server (8 or 12 cores, 72 GB RAM, FC 4 Gbit, etc...) and good storage?
300 Millions in only one table with 500K transactions / day is too much?
In my production ENV there is two node RAC database is running , and on both machine RAM size is (35GB on node1,41GB on Node2) and other configuration is like below.
I wish to run a SQL query and measure elapsed time, then compare the values to other Oracle DBs from other companies. That will give me a feeling if our DB performs well.For example in UNIX world, you can create a random 4GB file to measure throughput I/O and compare the values (for example 4MB/sec).
What's the simplest way to compare DB response time from forum members to our own DB? I don't need 100% accurate numbers.
I am trying to generate AWR report for database observation. But I am not getting any snapshot listed there. below is the output of my awrrpt.sql
SQL> @?/rdbms/admin/awrrpt.sql
Current Instance ~~~~~~~~~~~~~~~~ DB Id DB Name Inst Num Instance ----------- ------------ -------- ------------ 1140984076 AFCCV 1 afccv
Specify the Report Type ~~~~~~~~~~~~~~~~~~~~~~~ Would you like an HTML report, or a plain text report?
Enter 'html' for an HTML report, or 'text' for plain text Defaults to 'html'
Enter value for report_type: html
Type Specified: html
Instances in this Workload Repository schema ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ DB Id Inst Num DB Name Instance Host ------------ -------- ------------ ------------ ------------ * 1140984076 1 AFCCV afccv SERVICEDB1
Using 1140984076 for database Id Using 1 for instance number
Specify the number of days of snapshots to choose from ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Entering the number of days (n) will result in the most recent (n) days of snapshots being listed. Pressing <return> without specifying a number lists all completed snapshots.
Enter value for num_days: 3
Listing the last 3 days of Completed Snapshots
Specify the Begin and End Snapshot Ids ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Enter value for begin_snap:
elapsed time = time spent on waits + time CPU was used
Total time during snaps = Elapsed time + (may be) time waited for CPU...In AWR is it possible to draw such equation? I can see that the AWR report has following elements
1) End Snap time - Begin Snap time 2) DB time - as mentioned at the top of AWR report 3) DB CPU - in "Top 5 Timed Foreground Events" (I assume this is 'CPU used by sesson timing' in statspack) 4) Total of time for all Statistics in "Time Model Statistics" 5) BUSY_TIME + IDLE_TIME - "Operating System Statistics"
Time between 2 snapshots? or what else? Also for which seconds to multiply to 'DB Time(s)' per second and 'DB CPU(s)' per second in Load Profile to get the db time and CPU time?
I would like to generate HTML awr report and save it to my local machine.
After running $ORACLE_HOME/rdbms/admin/awrrpt.sql in sqlplus and specifying HTML in (Enter value for report_type: HTML) i hvae get numerous html code in my sqlplus prompt.. I want to save the html report in local machine and open it by double clicking on it.. it will be opened in a browser..
I understand that when data is read from the disk, I/O is done..And When computations are done then CPU is used..Then where the following equation fits?
A coworker of mine asked if there was any documentation from Oracle that listed all of the parts of the AWR report and what each meant. I was taken back because I don't think there is. There are third party books that talk about AWR reports and their predecessor Statspack reports.
Oracle has some notes on their support site about reading an AWR or Statspack report. All I found in the official documentation was some basic information about how to run an AWR report and an overview of what it was. It would be nice to have some sort of documentation that lists out each section and explains the units and purpose.
Is it possible to generate AWR report for the duration of 5 min? As we know that snapshots are generated for every 1 hour, which we specified in parameter.
By changing the parameter to 2 min, what could be the impact on database?
I ran an AWR report. The database looks fine, but a data load that loaded 1 Million rows an hour is now doing 500K per hour.
Wait Class Waits %Time -outs Total Wait Time (s) Avg wait (ms) %DB time DB CPU 224 80.70 Other 2,668 0 28 10 9.99 System I/O 4,753 0 9 2 3.23 Administrative 1 0 6 5543 2.00 Commit 357 0 4 11 1.46
[code]....
The network value for wait: 630,601. What does this mean? Anything I should look at? When it was 1million per hour, the value was 4,563,000.
Top 5 Timed Foreground Events
Event Waits Time(s) Avg wait (ms) % DB time Wait Class DB CPU 224 80.70 unspecified wait event 2,666 28 10 9.99 Other control file sequential read 4,753 9 2 3.23 System I/O switch logfile command 1 6 5543 2.00 Administrative log file sync 357 4 11 1.46 Commit
We are using 11.2.0.3.0 on solaris 10 facing slow performance, following are the Wait Events in AWR report, Also if any specific document to analyze AWR report and to pin point the performance bottleneck.
Foreground Wait Events ********************** Avg %Time Total Wait wait Waits % DB Event Waits -outs Time (s) (ms) /txn time -------------------------- ------------ ----- ---------- ------- -------- ------ direct path read 308,729 0 21,191 69 58.0 39.5 db file sequential read 208,754 0 3,742 18 39.2 7.0 cursor: pin S 19,541,899 0 2,561 0 3,668.5 4.8 [code]....
change the color of a row in APEX SQL report. Change Colour of Row - Oracle APEX SQL Report...It's a bit outdated, and trying to figure out how to get to this page: URL.....where I can conditionally set background color.
I am using theme 13 (legacy) and made a copy of the report region. Edited it but cannot find an equivalent section of that apex 3.1 screenshot.
Looking to understand the difference between instance tuning and database tuning.
What is the difference between these two tuning exercises? I understand that an instance is memory based structures (logical) where as database consists of physical structures.
However, how does one tune a database the physical structure? Does it have to do with file placements/block sizes etc. Would you agree that a lot of that is taken care by ASM now in 11g? What tools are required/available (third party as well as oracle supplied) for these types of tuning scenarios?
I have two tables with 113M records in DWH_BILL_DET & 103M in prd_rerate_chg_que and Im running following merge query, which is running for 13 hrs to update records, which is quiet longer time.
SQL> explain plan for MERGE /*+ parallel (rq, 16) */ INTO DWH_BILL_DET rq USING (SELECT rated_que_rowid, detail_rerate_flag_code, rerate_sel_key,
How the length of column width effects index performance?
For example if i had IOT table emp_iot with columns: (id number, job varchar2(20), time date, plan number)
Table key consist of(id, job, time)
Column JOB has fixed list of distinct values ('ANALYST', 'NIGHT_WORKED', etc...).
What performance increase i could expect if in column "job" i would store not names but concrete numbers identifying job names. For e.g. i would store "1" instead 'ANALYST' and "2" instead 'NIGHT_WORKED'.
I have a question about database fragmentation.I know that fragmentation can reduce performance in query times. The blocks are distributed in many extents and scans process takes a long time. Oracle engine have to locate the address of the next extent..
I want to know if there is any system view in which you can check if your table or index has high fragmentation. If it's needed I will have to re-create, move or rebulid the table or index, but before I want to know if the degree of fragmentation is high.
Any useful script or query to do this, any interesting oracle system view?
There is a simple way to increase the performance of a query by reducing the row-size of the table it hits. I used it in the past by dividing the table into smaller parts and querying respective smaller table in each query.
what is this method called ? just forgot the method and can't recall it. what this type of row-reduction optimization is called ?
Testing our 9i to 11g upgrade, we've imported the entire DB into the new machine.We've found that certain procedures are really suffering performance problems. BUT, we've also found, that if we check out a production copy of the procedure from our source code control, and reinstall it, the performance issue goes away. Just alter the procedure and recompiling does NOT work.
The new machine where the 11g database exists is slightly different than the source, but it's not like we have this problem with every procedure. It's only a couple.
any possible reason that we'd have to re-install a procedure to correct a performance problem?
I need to check the package performance and need to improve the package performance.
1. how to check the package performance(each and every statement in the package)? 2. In the package using the delete statement to delete all records and observed that delete is taking long time to delete all the records in the table(Table records 7000000). This table is like staging table.Daily need to clean the data before inserting the data into it. what can I use instead of Delete.
Somewhere I read that we should not use hints in Oracle production environments, but we can use hints in the development environment and on achieving the desired execution plan we can adjust the 'statistics' to follow that plan without hints.
Q1. If it is true what statistics do we adjust for influencing the execution plan and how?
For example, I have the following simple query:
select e.empid, e.ename, d.dname from emp e, dept d where e.deptno=d.deptno;
emp.empid, emp.deptno and dep.deptno columns have indexes and the tables have the standard structure as found in the basic oracle examples.
If I look at the execution plan of the above query then I see that the driving table is empand the driven table is dept.Also the type of join that is taking place is 'Nested Loop'.
Questions: With respect to the above query, Q 2. If I want to make dept the driving table and emp the driven table then how can I adjust the statistics to achieve that? Q 3. If I want to use hash join instead of a nested loop join then then how can I adjust the statistics to achieve that?
I can put the ordered and the use_hash hint to effect this but again I have heard that altering statistics is a more robust way to control an execution plan as compared to hints.