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Home -> Community -> Mailing Lists -> Oracle-L -> RE: INITIAL and NEXT extent sizing question
Hi
Correct me if I am wrong but
Besides the fragmentation reason I think by have a few extents you can =
distribute your IO across different disks.
So create large enough extents on different disks to spread you IO as =
opposed to having 1 very large extent on 1 disk.
HTH
Suhen
>>> RROGERS_at_galottery.org 09/27/00 03:55PM >>>
The theory behind uniform init and entents is the reduction of fragmentatio=
n and wasted space. If you use 1 large extent and then truncate the table =
a lot of small extents can reuse the space freed up but is the extent =
sizes are a mixed bag then the space usage can and will leave a lot of =
holes that are not big enough for an extent. Thus fragmentation.
ROR =AA=BF=AA
>>> Deepender_Gupta_at_escorts.co.in 09/27/00 08:55AM >>>
But Oracle says that we try to have our table in not more than 5 extents.
What is the advantage of having more extents of smaller size as opposed =
to
having 1 big
extent.
Kindly elaborate.
Deepender
To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>@SMTP_at_AMG1=
cc:
Hi
It would all depend on the table. If the table is not going to grow
then the NEXT should be set low (Hence the table would not extend).
If the table would be continually growing then the NEXT should be
sized accordingly to allow for inserts.
Try not to make the NEXT too big (>1GB)
eg. You rather have 4 * 500M extents as opposed to having 1 * 4GB
extent.
HTH
Suhen
>>> Venkat_Kalepalli_at_satyam.com 09/26/00 02:51PM >>>
I think U can set NEXT also same as INITIAL.
Venkat
Ph:7846101- Extn: 5648
> ----------
> From: Fred Smith[SMTP:fred_fred_1_at_hotmail.com]=20
> Reply To: ORACLE-L_at_fatcity.com=20
> Sent: Monday, September 25, 2000 10:05 PM
> To: Multiple recipients of list ORACLE-L
> Subject: INITIAL and NEXT extent sizing question
>
> I have a table with rows currently populating. I wish to resize the
table
>
> for better performance. What is the best way I should figure out how
to
> size my INITIAL and NEXT extent sizes for this table. Is it just:
> 1) Analyze the table
> 2) SELECT BLOCKS * (block_size) from dba_tables for the table in
question
> =3D
> what the initial size should be set to.
> 3) What determines what I should set the NEXT extent size to then?
>
> Thank you,
> -Fred S.
>
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com=20 -- Author: Suhen Pather INET: PatherS5_at_telkom.co.za=20 Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- 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). --=20 Please see the official ORACLE-L FAQ: http://www.orafaq.com=20 --=20 Author:=20 INET: Deepender_Gupta_at_escorts.co.in=20 Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- 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.com=20 -- Author: Ron Rogers INET: RROGERS_at_galottery.org=20 Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- 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 Wed Sep 27 2000 - 08:25:11 CDT
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