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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Locally managed tablespaces
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"The gain from that change was about 2%."
Steve, What metric did you use?
Did you use a task or customer-specific metric (in which case the 2% gain does not necessarily map over to anyone else's site) or a generic "benchmark" you picked up in your travels ( in which case it might be of general use to us listers <g> )
-----Original Message-----
From: Steve Adams [mailto:steve.adams_at_ixora.com.au]
Sent: Tuesday, January 30, 2001 6:10 PM
To: Multiple recipients of list ORACLE-L
Subject: RE: Locally managed tablespaces
Hi All,
I was working on a tuning assignment last week where one of the more minor
changes made was to migrate their "scratch" tablespace to locally managed.
The
gain from that change was about 2%. That saving was due to the elimination
of ST
enqueue contention associated with multiple processes trying to create
scratch
tables at the same time.
It is only certain data dictionary queries that are slower with locally
managed
tablespaces, and that's only really bad if you have too many extents per
segment. See http://www.ixora.com.au/tips/creation/extents.htm for why. The
performance of SELECT and DML statements against user data is unchanged. The
performance of space management transactions is slightly improved, and
greatly
if ST enqueue contention was otherwise a problem.
@ Regards, @ Steve Adams @ http://www.ixora.com.au/ @ http://www.christianity.net.au/
-----Original Message-----
Sent: Wednesday, 31 January 2001 5:11
To: Multiple recipients of list ORACLE-L
Has anyone taken a PROD DB and changed it to using LMTSs and then noticed a
perf
change + or -?
--- TheOracleDBA theoracledba_at_lycos.com On Tue, 30 Jan 2001 10:30:29 Bunyamin K.Karadeniz wrote:Received on Wed Jan 31 2001 - 09:39:22 CST
> But some had claimed that Locally managed tablespaces are slower. I do
>not know if it is correct but you must consider it . > And I wonder the performance results too. > >----- Original Message ----- >To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> >Sent: Tuesday, January 30, 2001 3:35 PM > > >> I have always been concerned with fragmentation of tablespaces, whether it >> be lots of extents, honeycomb or >> bubble fragmentation. Now I am reading that in Oracle 8i with the use of >> locally-managed table spaces, >> these concerns are a thing of the past as Oracle now uses bit maps within >> the tablespaces themselves to >> do space management. This seems foreign to me that even though Oracle will >> use up all the space in >> the tablespaces with no coalescing, it is OK that extents will go into >the >> thousands with no performance degradation. >> Could folks who are currently using locally managed tablespaces please >> comment on how well it >> is working for them and if they have experienced any problems in using >them. >> Thanks >> Skip -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Steve Adams INET: steve.adams_at_ixora.com.au 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). ------_=_NextPart_001_01C08B9B.FB6F21D0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> <HTML> <HEAD> <META HTTP-EQUIV=3D"Content-Type" CONTENT=3D"text/html; = charset=3Diso-8859-1"> <META NAME=3D"Generator" CONTENT=3D"MS Exchange Server version = 5.5.2653.12"> <TITLE>RE: Locally managed tablespaces</TITLE> </HEAD> <BODY> <P><FONT SIZE=3D2>"The gain from that change was about = 2%."</FONT> </P> <P><FONT SIZE=3D2>Steve, What metric did you use? </FONT> </P> <P><FONT SIZE=3D2>Did you use a task or customer-specific metric = </FONT> <BR><FONT SIZE=3D2>(in which case the 2% gain does not necessarily map = </FONT> <BR><FONT SIZE=3D2>over to anyone else's site) or a generic = "benchmark" </FONT> <BR><FONT SIZE=3D2>you picked up in your travels ( in which case it = </FONT> <BR><FONT SIZE=3D2>might be of general use to us listers <g> = )</FONT> </P> <P><FONT SIZE=3D2>- Ross</FONT> </P> <P><FONT SIZE=3D2>-----Original Message-----</FONT> <BR><FONT SIZE=3D2>From: Steve Adams [<A = HREF=3D"mailto:steve.adams_at_ixora.com.au">mailto:steve.adams_at_ixora.com.au= </A>]</FONT> <BR><FONT SIZE=3D2>Sent: Tuesday, January 30, 2001 6:10 PM</FONT> <BR><FONT SIZE=3D2>To: Multiple recipients of list ORACLE-L</FONT> <BR><FONT SIZE=3D2>Subject: RE: Locally managed tablespaces</FONT> </P> <BR> <P><FONT SIZE=3D2>Hi All,</FONT> </P> <P><FONT SIZE=3D2>I was working on a tuning assignment last week where = one of the more minor</FONT> <BR><FONT SIZE=3D2>changes made was to migrate their = "scratch" tablespace to locally managed. The</FONT> <BR><FONT SIZE=3D2>gain from that change was about 2%. That saving was = due to the elimination of ST</FONT> <BR><FONT SIZE=3D2>enqueue contention associated with multiple = processes trying to create scratch</FONT> <BR><FONT SIZE=3D2>tables at the same time.</FONT> </P> <P><FONT SIZE=3D2>It is only certain data dictionary queries that are = slower with locally managed</FONT> <BR><FONT SIZE=3D2>tablespaces, and that's only really bad if you have = too many extents per</FONT> <BR><FONT SIZE=3D2>segment. See <A = HREF=3D"http://www.ixora.com.au/tips/creation/extents.htm" = TARGET=3D"_blank">http://www.ixora.com.au/tips/creation/extents.htm</A> = for why. The</FONT> <BR><FONT SIZE=3D2>performance of SELECT and DML statements against = user data is unchanged. The</FONT> <BR><FONT SIZE=3D2>performance of space management transactions is = slightly improved, and greatly</FONT> <BR><FONT SIZE=3D2>if ST enqueue contention was otherwise a = problem.</FONT> </P> <P><FONT SIZE=3D2>@ Regards,</FONT> <BR><FONT SIZE=3D2>@ Steve Adams</FONT> <BR><FONT SIZE=3D2>@ <A HREF=3D"http://www.ixora.com.au/" = TARGET=3D"_blank">http://www.ixora.com.au/</A></FONT> <BR><FONT SIZE=3D2>@ <A = HREF=3D"http://www.christianity.net.au/" = TARGET=3D"_blank">http://www.christianity.net.au/</A></FONT> </P> <BR> <P><FONT SIZE=3D2>-----Original Message-----</FONT> <BR><FONT SIZE=3D2>Sent: Wednesday, 31 January 2001 5:11</FONT> <BR><FONT SIZE=3D2>To: Multiple recipients of list ORACLE-L</FONT> </P> <BR> <P><FONT SIZE=3D2>Has anyone taken a PROD DB and changed it to using = LMTSs and then noticed a perf</FONT> <BR><FONT SIZE=3D2>change + or -?</FONT> </P> <P><FONT SIZE=3D2>---</FONT> </P> <P><FONT SIZE=3D2>TheOracleDBA</FONT> <BR><FONT SIZE=3D2>theoracledba_at_lycos.com</FONT> </P> <BR> <BR> <P><FONT SIZE=3D2>On Tue, 30 Jan 2001 10:30:29</FONT> <BR><FONT SIZE=3D2> Bunyamin K.Karadeniz wrote:</FONT> <BR><FONT SIZE=3D2>> But some had claimed that = Locally managed tablespaces are slower. I do</FONT> <BR><FONT SIZE=3D2>>not know if it is correct but you must = consider it .</FONT> <BR><FONT SIZE=3D2>> And I wonder the performance results = too.</FONT> <BR><FONT SIZE=3D2>></FONT> <BR><FONT SIZE=3D2>>----- Original Message -----</FONT> <BR><FONT SIZE=3D2>>To: Multiple recipients of list ORACLE-L = <ORACLE-L_at_fatcity.com></FONT> <BR><FONT SIZE=3D2>>Sent: Tuesday, January 30, 2001 3:35 PM</FONT> <BR><FONT SIZE=3D2>></FONT> <BR><FONT SIZE=3D2>></FONT> <BR><FONT SIZE=3D2>>> I have always been concerned with = fragmentation of tablespaces, whether it</FONT> <BR><FONT SIZE=3D2>>> be lots of extents, honeycomb or</FONT> <BR><FONT SIZE=3D2>>> bubble fragmentation. Now I am reading that = in Oracle 8i with the use of</FONT> <BR><FONT SIZE=3D2>>> locally-managed table spaces,</FONT> <BR><FONT SIZE=3D2>>> these concerns are a thing of the past as = Oracle now uses bit maps within</FONT> <BR><FONT SIZE=3D2>>> the tablespaces themselves to</FONT> <BR><FONT SIZE=3D2>>> do space management. This seems foreign to = me that even though Oracle will</FONT> <BR><FONT SIZE=3D2>>> use up all the space in</FONT> <BR><FONT SIZE=3D2>>> the tablespaces with no coalescing, = it is OK that extents will go into</FONT> <BR><FONT SIZE=3D2>>the</FONT> <BR><FONT SIZE=3D2>>> thousands with no performance = degradation.</FONT> <BR><FONT SIZE=3D2>>> Could folks who are currently using locally = managed tablespaces please</FONT> <BR><FONT SIZE=3D2>>> comment on how well it</FONT> <BR><FONT SIZE=3D2>>> is working for them and if they have = experienced any problems in using</FONT> <BR><FONT SIZE=3D2>>them.</FONT> <BR><FONT SIZE=3D2>>> Thanks</FONT> <BR><FONT SIZE=3D2>>> Skip</FONT> </P> <P><FONT SIZE=3D2>-- </FONT> <BR><FONT SIZE=3D2>Please see the official ORACLE-L FAQ: <A = HREF=3D"http://www.orafaq.com" = TARGET=3D"_blank">http://www.orafaq.com</A></FONT> <BR><FONT SIZE=3D2>-- </FONT> <BR><FONT SIZE=3D2>Author: Steve Adams</FONT> <BR><FONT SIZE=3D2> INET: steve.adams_at_ixora.com.au</FONT> </P> <P><FONT SIZE=3D2>Fat City Network Services -- (858) = 538-5051 FAX: (858) 538-5051</FONT> <BR><FONT SIZE=3D2>San Diego, = California -- Public Internet = access / Mailing Lists</FONT> <BR><FONT = SIZE=3D2>---------------------------------------------------------------= -----</FONT> <BR><FONT SIZE=3D2>To REMOVE yourself from this mailing list, send an = E-Mail message</FONT> <BR><FONT SIZE=3D2>to: ListGuru_at_fatcity.com (note EXACT spelling of = 'ListGuru') and in</FONT> <BR><FONT SIZE=3D2>the message BODY, include a line containing: UNSUB =
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