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RE: Block dump - Uncommitted TXN - Help Urgent

From: Bobak, Mark <>
Date: Wed, 20 Sep 2006 12:13:30 -0400
Message-ID: <>

Note that if you see a TX enqueue waiting on mode 4, that's not necessarily ITL slot shortage. If the waiting statement is an INSERT and the object is a heap table, then it's definitely not ITL shortage. (If there's ITL shortage on a table block, INSERT will go to another block on the free list, if it's on the index, INSERT will do a block split.)  

The other cause TX enqueue mode 4 waits is concurrent inserts colliding on a unique index, PK, or UK. (i.e. session 1 inserts key value 1, session 2 inserts value 2, session 1 attempts to insert value 2, session 2 attempts to insert value 1)  

Hope that helps,  


Mark J. Bobak 
Senior Oracle Architect 
ProQuest Information & Learning 

"A human being should be able to change a diaper, plan an invasion,
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[] On Behalf Of BN
Sent: Wednesday, September 20, 2006 10:15 AM
To: goran bogdanovic
Subject: Re: Block dump - Uncommitted TXN - Help Urgent

On 9/20/06, goran bogdanovic <> wrote: 

	The inittrans should correspond to your max active concurrent
dml sessions on that table
	On 9/20/06, BN < <> >

		On 9/19/06, Christian Antognini <
<> > wrote: 

> I was thinking of INITRANS , is there a way to
track that from
> v$lock,
> I remember once Steve Adams answering some
body looking at v$lock
> looking at Request Column, not sure though
Hi Here an example of sessions waiting for a transaction slot: SQL> SELECT event FROM v$session_wait WHERE sid = 12; EVENT ----------- enqueue SQL> SELECT type, id1, id2, lmode, request FROM v$lock WHERE sid = 12; TY ID1 ID2 LMODE REQUEST -- ---------- ---------- ---------- ---------- TM 34522 0 3 0 TX 393247 9877 0 4 As you can see the request mode is S (4). HTH Chris -- Greetings, Yes I saw Request=4 for quite a few sessions. I ahve Identified the Tables that needs INITRANS Bump. Is there a way to figureout how much should I bump for each table in question -- Regards & Thanks BN Greetings Yes, I understand, is there a view in the Datadictionary to check how much each table has reached, other than tracking/sampling v$lock or v$transaction -- Regards & Thanks BN --
Received on Wed Sep 20 2006 - 11:13:30 CDT

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