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Home -> Community -> Mailing Lists -> Oracle-L -> KEEP creep - CR copy of the block
blocks from the rollback segment are also cached in db_block_buffer,
is the CR copy of the block maps to the rollback block ?
because for CR, a process will read the rollback block to re-create the snapshot.
> ----------
> From: Steve Adams[SMTP:steve.adams_at_ixora.com.au]
> Reply To: ORACLE-L_at_fatcity.com
> Sent: Friday, August 11, 2000 3:26 AM
> To: Multiple recipients of list ORACLE-L
> Subject: RE: KEEP creep
>
> Hi Alex,
>
> I presume that's a typo. It is CR blocks, not CR locks. Sorry if the
> previous message was a bit cryptic. I was about to go to bed, and I knew
> that Mark would still be at work and would appreciate a quick answer. I
> also knew that he would understand. Anyway, CR means consistent read. A
> CR block is a temporary copy of the current mode block that has been
> rolled back for the purposes of read consistency. The parameter setting
> causes CR blocks to be placed at the LRU end of the cache where they
> will be immediately reused once unpinned.
>
> Regards,
> Steve Adams
> http://www.ixora.com.au/
> http://www.oreilly.com/catalog/orinternals/
> http://www.christianity.net.au/
>
>
> -----Original Message-----
> Sent: Friday, 11 August 2000 3:19
> To: Multiple recipients of list ORACLE-L
>
>
> Could you elaborate a little bit please - what is CR locks, when they
> happen and what consequences of using this parameter.
> Alex Hillman
> -----Original Message-----
> Sent: Thursday, August 10, 2000 7:34 AM
> To: Multiple recipients of list ORACLE-L
>
>
> Hi Mark,
> There is no such timeout. What you are seeing is the effect of CR mode
> blocks.
> You should be able to work around this by setting _db_aging_freeze_cr =
> TRUE.
> Regards,
> Steve Adams
> http://www.ixora.com.au/
> http://www.oreilly.com/catalog/orinternals/
> http://www.christianity.net.au/
>
>
> -----Original Message-----
> Sent: Thursday, 10 August 2000 19:33
> To: Multiple recipients of list ORACLE-L
Received on Fri Aug 11 2000 - 00:59:09 CDT