How to resolve wait event

according to statspack report top five waits events are:-
Event Waits Time (s) Ela Time
db file sequential read 15,496 651 55.53
CPU time 470 40.09
control file parallel write 643 15 1.26
log file sync 518 13 1.14
db file parallel write 252 10 .85
But how can i resolve these events.Please help me. I am not well aware about tuning aspect.
Thanks in advance

You input is very restricted, no one can't really advice on this. You would have given more info.
As you can see, 'db file sequential read' is the top most wait event. Which mean, you are using wrong index or index doesn't required. Look at the top sqls in the stats pack nd tune them.
This also due to the fact the your index statsitics are not providing enough good info to optimizer.
Jaffar

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How to resolve Library Cache Pin waits?

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How to resolve PL/SQL lock timer event

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http://hemantoracledba.blogspot.com
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Edited by: Hemant K Chitale on Jul 31, 2009 12:08 AM

Wait events - how to read it

Hi frnds,
As, I'm beginner to performance tuning I dont know
What action do i need to take?
I mean how to read the output which I given below.
this is the output suffering buffer busy waits.
Could anyone please tell me
CLASS TOTAL_WAITS TOTAL_TIME
data block 93303 58711
unused 0 0
system undo header 12 232
undo header 7847 6636
3rd level bmb 0 0
save undo header 0 0
bitmap index block 0 0
file header block 0 0
free list 0 0
undo block 68 207
segment header 422 399
extent map 0 0
2nd level bmb 0 0
system undo block 0 0
sort block 0 0
save undo block 0 0
1st level bmb 1 17
bitmap block 0 0
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Hello,
"Buffer busy waits" is contention for a buffer (representing a specific
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the design of the tables and indexes supporting the application. A
built-in bottleneck. On indexes, it could be the age-old problem of
insertions into an index on a column with a monotonically-ascending
data value (i.e. timestamps or sequence numbers) which tends to cause
contention on the highest leaf node of the index. On tables, it might
have to do with many concurrent insertions into a table in a
freelist-managed tablespace where the table has only one freelist. It
could also be due to a home-grown implementation of sequence-number
generators (i.e. small table with one row, one column in which contains
the "last value" of a sequence, etc) which lots of people use to avoid
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relatively low CPU time, indicating a lot of wait time. Of course,
there are something like 800 possible wait events in current releases
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inference and not a direct causal connection to your problem. But,
once I find such statements I'd check to see if they are
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use "select * from table(dbms_xplan.display_awr('sql-id'))" to
get the execution plan(s), and then look for something ineffective
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here as well, to get a "historical perspective" on the execution of the
SQL statements over time, in case the buffer busy waits peaked at some
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http://www.pubbs.net/201003/oracle/51925-understanding-awr-buffer-waits.html
Also
http://www.remote-dba.net/oracle_10g_tuning/t_buffer_busy_waits.htm
kind regards
Mohamed

How to see the wait events info. after excute a select query

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SELECT * FROM emp, dept
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Parse      1     0.16      0.29         3       13       0       0
Execute    1     0.00      0.00         0        0       0       0
Fetch      1     0.03      0.26         2        2       4      14
Misses in library cache during parse: 1
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SQL*Plus: Release 10.2.0.2.0 - Production on Wed Apr 20 15:29:33 2011
Copyright (c) 1982, 2005, Oracle. All Rights Reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - Production
With the Partitioning, OLAP and Data Mining options
SQL> SHOW PARAMETER dump
NAME                                 TYPE        VALUE
background_core_dump                 string      partial
background_dump_dest                 string      /user/oracle/app/oracle/admin/
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core_dump_dest                       string      /user/oracle/app/oracle/admin/
                                                 orclsb/cdump
max_dump_file_size                   string      UNLIMITED
shadow_core_dump                     string      partial
user_dump_dest                       string      /user/oracle/app/oracle/admin/
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Session altered.
SQL> SELECT * FROM emp WHERE deptno=20;
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      7369 SMITH      CLERK           7902 17-DEC-80        800
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      7902 FORD       ANALYST         7566 03-DEC-81       3000
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TKPROF: Release 10.2.0.2.0 - Production on Wed Apr 20 15:32:17 2011
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Hello,
I created a workflow starting from a form: the user can chose a production order number.
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When the event BUS2005-DELETE is raising I have to finish the workflow but only if the event is raising for the
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Hello Roberto Baldassarre !
To instantiate your BOR, release it and do the event binding at workflow and also the binding at wait step perfectly.
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Can you please tell me how to find top 10 wait events

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Thanks
Regards,
RJ.

hi,
suggest you to use statspack !!!!!!! for the all tuning..else use the views
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http://www.dba-oracle.com/art_dbazine_waits.htm
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Wait events and locks monitoring /resolving scripts

Looking for wait events and locks monitoring /resolving scripts /tips.

Hi,
Looking for wait events and locks monitoring /resolving scriptsHere is the collection of monitoring scripts that I
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http://www.oracle-script.com
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SET LINESIZE 500
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COLUMN username FORMAT A15
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sb92075 wrote:
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We are trying to figure out root cause of slow running sql server queries hitting/fetching data from one of the database , size 300 GB, hosted on server with below configuration:
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Sachin.Ichake wrote:
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How to resolve wait event

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