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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Calculating new PCTFREE and PCTUSED !!!!!1
Dennis,
My database is of size 960 Gig for now and its a heavy OLTP with high DML activity on tables , we are observing some ORA-00600 errors these days due to chained rows in the tables . Also we all know chained rows cause performance issues . I wanted to fix this ASAP and also would like to alter the PCTFREE , so I want some ideas from all of you to find out a proper value ..
Thanks
Madhu
-----Original Message-----
Sent: Friday, January 17, 2003 3:04 PM
To: Multiple recipients of list ORACLE-L
Reddy - No I have not used that script. But most of Don's stuff is quite good. I thought it might illuminate some issues for you. Sorry if it didn't help.
The PCTFREE and PCTUSED parameters mainly need tweaked when your data is volatile, when existing rows are updated with additional data. Is your data very volatile?
Dennis Williams
DBA, 40%OCP
Lifetouch, Inc.
dwilliams_at_lifetouch.com
-----Original Message-----
Sent: Friday, January 17, 2003 12:50 PM
To: Multiple recipients of list ORACLE-L
Dennis,
Have you used the script ??
I have gone thru the material u have pointed , also executed the script in it, but it doesn't make any sense to me . Performance is the issue for me not the SPACE .
here is the script:
spool pctused.lst;
define spare_rows = 2;
define blksz = 4096; ( I used 8192 )
select
' alter table '||owner||'.'||table_name|| ' pctused '||least(round(100-((&spare_rows*avg_row_len)/(&blksz/10))),95)|| ' '|| ' pctfree '||greatest(round((&spare_rows*avg_row_len)/(&blksz/10)),5)|| ';'
spool off;
Sample o/p: alter table <schema>.TSFDETAIL pctused 95 pctfree 5;
And previous value for PCTFREE is 20 and the chained rows are 1054757 in that table..
Does anyone have good idea to calculate PCTFREE would like to share with me ???
I need help !!!
Thanks
Madhu
-----Original Message-----
Sent: Wednesday, January 15, 2003 3:26 PM
To: Multiple recipients of list ORACLE-L
Madhu
Here is a good article that discusses the various aspects: http://www.dba-oracle.com/art_pctfree.htm
Dennis Williams
DBA, 40%OCP
Lifetouch, Inc.
dwilliams_at_lifetouch.com
-----Original Message-----
Sent: Wednesday, January 15, 2003 3:06 PM
To: Multiple recipients of list ORACLE-L
Hello All,
I have found some of the tables are heavily chained in one of the database .
I want to fix them by exp and imp, but before that I would like to have a
formula or some better method to identify the new PCTFREE and PCTUSED for
each individual table.
Many of you have might have done this in the past , would you pl share your ideas on this ??
Thanks in advance,
Madhu
-- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Reddy, Madhusudana INET: Madhusudana.Reddy_at_bestbuy.com Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-LReceived on Fri Jan 17 2003 - 15:49:34 CST
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also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Reddy, Madhusudana INET: Madhusudana.Reddy_at_bestbuy.com Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L
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also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: DWILLIAMS_at_LIFETOUCH.COM Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from). You may
also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Reddy, Madhusudana INET: Madhusudana.Reddy_at_bestbuy.com Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from). You may
also send the HELP command for other information (like subscribing).
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