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Home -> Community -> Mailing Lists -> Oracle-L -> Re: production database on aix won't be open, help
>> I had meant Deferred Transaction Rollback which enables a database to be
opened as soon as the roll forward
using the redo log file is completed.
I thought deferred transaction rollback had only to do with storing
rollback information for offline tablespaces. What am I missing? Or is the
terminology confusing me?
Raj
"Danisment
Gazi Unal To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
(ubTools)" cc:
<dunal_at_ubTool Subject: Re: production database on aix won't be open, help
s.com>
Sent by:
root_at_fatcity.
com
June 19, 2002
05:37 PM
Please
respond to
ORACLE-L
Yes,
These are right too. But, I think, these are related to fast start parallel rollback.
I had meant Deferred Transaction Rollback which enables a database to be
opened as soon as the roll forward
using the redo log file is completed.
I think we are saying same thing on different topics.
regards...
Rajesh.Rao_at_jpmchase.com wrote:
> Yup. FYI, this is what Metalink says:
>
> A
final new feature for
>
specifying bounded recovery time
> is the
use of fast-start
>
parallel rollback. In prior
>
versions of Oracle, although
>
database recovery time was
>
reduced because Oracle could
> open
the database after the
>
instance roll-forward process
>
completed, the transaction
>
rollback could still take a long
> time,
particularly for parallel
> DML
operations, because rollback
> had to
happen serially. In
>
Oracle8i, you can specify the
>
FAST_START_PARALLEL_ROLLBACK
>
parameter to low or high to
> allow
SMON to use parallel-query
> slaves
for parallel rollback,
> thus
speeding up the rollback
>
process. Monitoring parallel
>
rollback can be accomplished
> using
the V$FAST_START_SERVERS
> and
V$FAST_START_TRANSACTIONS
> views.
>
>
> And on Technet:
>
> Fast-start parallel rollback is mainly useful when a system has
> transactions that run a long time before committing, especially parallel
> INSERT, UPDATE, and DELETE operations. When SMON discovers that the
amount
> of recovery work is above a certain threshold, it automatically begins
> parallel rollback by dispersing the work among several parallel
processes:
> process 1 rolls back one transaction, process 2 rolls back a second
> transaction, and so on. The threshold is the point at which parallel
> recovery becomes cost-effective, in other words, when parallel recovery
> takes less time than serial recovery.
>
> One special form of fast-start parallel rollback is intra-transaction
> recovery. In intra-transaction recovery, a single transaction is divided
> among several processes. For example, assume 8 transactions require
> recovery with one parallel process assigned to each transaction. The
> transactions are all similar in size except for transaction 5, which is
> quite large. This means it takes longer for one process to roll this
> transaction back than for the other processes to roll back their
> transactions.
>
> In this situation, Oracle automatically begins intra-transaction recovery
> by dispersing transaction 5 among the processes: process 1 takes one
part,
> process 2 takes another part, and so on.
>
> You control the number of processes involved in transaction recovery by
> setting the parameter FAST_START_PARALLEL_ROLLBACK to one of three
values:
>
> FALSE Turns off fast-start parallel rollback.
>
> LOW Specifies that the number of recovery servers may not exceed twice
> the value of the CPU_COUNT parameter.
>
> HIGH Specifies that the number of recovery servers may not exceed four
> times the value of the CPU_COUNT parameter.
>
>
> Regards
> Raj
>
>
> "Danisment
> Gazi Unal To: Multiple recipients of
list ORACLE-L <ORACLE-L_at_fatcity.com>
> (ubTools)" cc:
> <dunal_at_ubTool Subject: Re: production
database on aix won't be open, help
> s.com>
> Sent by:
> root_at_fatcity.
> com
>
>
> June 19, 2002
> 04:27 PM
> Please
> respond to
> ORACLE-L
>
>
>
> Hello Rajesh,
>
> You are definitly right. But, as I know Deffered Transaction Rollback
> feature is intruduced with 7.3.
>
> Also,
>
> there is a good enhancement in 8i which enables SMON to use parallel
query
> slaves automatically to complete
> rollback operation. Current threshold for that is 100 rollback blocks.
>
> Rajesh.Rao_at_jpmchase.com wrote:
>
> > Sorry, but does Oracle not do the rollback in the background, reading
> > records from undo$. This is a feature called fast warmstart, introduced
> > with 8.0. During an instance recovery, a roll forward is done, and the
> > database opened for normal operations. A rollback is done in the
> > background.
> >
> > Raj
> >
> >
> > "Charlie
> > Mengler" To: Multiple recipients of
> list ORACLE-L <ORACLE-L_at_fatcity.com>
> > <charliem_at_mwh cc:
> > .com> Subject: Re: production
> database on aix won't be open, help
> > Sent by:
> > root_at_fatcity.
> > com
> >
> >
> > June 19, 2002
> > 01:28 PM
> > Please
> > respond to
> > ORACLE-L
> >
> >
> >
> > It might be that Oracle is simply trying to rollback a _BIG_
uncommitted
> > transaction.
> > Once in the past I had a similar problem. The fix was amazingly simple.
I
> > increased
> > the size of the TEMP tablespace. I suspect that if you are really,
> really,
> > really
> > patient Oracle eventually will wake from its slumber & begin normal
> > operations.
> >
> > HTH & YMMV,
> >
> > HAND!
> >
> > chal_ping wrote:
> > >
> > > oracle-lHi, grurus:
> > > This is a production database 8.1.7.2 on aix 4.3.3, there are
> 17
> > instances running on the same box.
> > > I shutdown immediate the database and it hangs.After wait for
> one
> > hour, i do a shutdown abort. When i startup again, it failed to open
the
> > database , just hangs at this stage like:
> > > Sun Jun 16 09:36:40 2002
> > > SMON: enabling cache recovery
> > > SMON: enabling tx recovery
> > > And the sql*plus window hangs at : database mounted, but
never
> > showed open.
> > > From another shell prompt, i sqlplus internal and query the
> > instance, it showed instance open in read write state!
> > > But from remote node via listener, client process showed
0134:
> > oracle not available.
> > > I once met such kind of questions on sun solaris, it is
because
> > of solaris bug.But never heard of this kind on AIX. Oracle support
> suggest
> > reboot the server, but as there is 16 other instance on it, it is not
the
> > solution.
> > > Can anyone help?
> > > Great thanks.
> > >
> > > --
> >
> > --
> > Please see the official ORACLE-L FAQ: http://www.orafaq.com
> > --
> > Author:
> > INET: Rajesh.Rao_at_jpmchase.com
> >
> > 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).
>
> --
> Danisment Gazi Unal
> http://www.ubTools.com
>
> --
> Please see the official ORACLE-L FAQ: http://www.orafaq.com
> --
> Author:
> INET: Rajesh.Rao_at_jpmchase.com
>
> 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).
-- Danisment Gazi Unal http://www.ubTools.com Yes, These are right too. But, I think, these are related to fast start parallel rollback. I had meant Deferred Transaction Rollback which enables a database to be opened as soon as the roll forward using the redo log file is completed. I think we are saying same thing on different topics. regards... Rajesh.Rao_at_jpmchase.com wrote: Yup. FYI, this is what Metalink says: A final new feature for specifying bounded recovery time is the use of fast-start parallel rollback. In prior versions of Oracle, although database recovery time was reduced because Oracle could open the database after the instance roll-forward process completed, the transaction rollback could still take a long time, particularly for parallel DML operations, because rollback had to happen serially. In Oracle8i, you can specify the FAST_START_PARALLEL_ROLLBACK parameter to low or high to allow SMON to use parallel-query slaves for parallel rollback, thus speeding up the rollback process. Monitoring parallel rollback can be accomplished using the V$FAST_START_SERVERS and V$FAST_START_TRANSACTIONS views. And on Technet: Fast-start parallel rollback is mainly useful when a system has transactions that run a long time before committing, especially parallel INSERT, UPDATE, and DELETE operations. When SMON discovers that the amount of recovery work is above a certain threshold, it automatically begins parallel rollback by dispersing the work among several parallel processes: process 1 rolls back one transaction, process 2 rolls back a second transaction, and so on. The threshold is the point at which parallel recovery becomes cost-effective, in other words, when parallel recovery takes less time than serial recovery. One special form of fast-start parallel rollback is intra-transaction recovery. In intra-transaction recovery, a single transaction is divided among several processes. For example, assume 8 transactions require recovery with one parallel process assigned to each transaction. The transactions are all similar in size except for transaction 5, which is quite large. This means it takes longer for one process to roll this transaction back than for the other processes to roll back their transactions. In this situation, Oracle automatically begins intra-transaction recovery by dispersing transaction 5 among the processes: process 1 takes one part, process 2 takes another part, and so on. You control the number of processes involved in transaction recovery by setting the parameter FAST_START_PARALLEL_ROLLBACK to one of three values: FALSE Turns off fast-start parallel rollback. LOW Specifies that the number of recovery servers may not exceed twice the value of the CPU_COUNT parameter. HIGH Specifies that the number of recovery servers may not exceed four times the value of the CPU_COUNT parameter. Regards Raj "Danisment Gazi Unal To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> (ubTools)" cc: <dunal_at_ubTool Subject: Re: production database on aix won't be open, help s.com> Sent by: root_at_fatcity. com June 19, 2002 04:27 PM Please respond to ORACLE-L Hello Rajesh, You are definitly right. But, as I know Deffered Transaction Rollback feature is intruduced with 7.3. Also, there is a good enhancement in 8i which enables SMON to use parallel query slaves automatically to complete rollback operation. Current threshold for that is 100 rollback blocks. Rajesh.Rao_at_jpmchase.com wrote: > Sorry, but does Oracle not do the rollback in the background, reading > records from undo$. This is a feature called fast warmstart, introduced > with 8.0. During an instance recovery, a roll forward is done, and the > database opened for normal operations. A rollback is done in the > background. > > Raj > > > "Charlie > Mengler" To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> > <charliem_at_mwh cc: > .com> Subject: Re: production database on aix won't be open, help > Sent by: > root_at_fatcity. > com > > > June 19, 2002 > 01:28 PM > Please > respond to > ORACLE-L > > > > It might be that Oracle is simply trying to rollback a _BIG_ uncommitted > transaction. > Once in the past I had a similar problem. The fix was amazingly simple. I > increased > the size of the TEMP tablespace. I suspect that if you are really, really, > really > patient Oracle eventually will wake from its slumber & begin normal > operations. > > HTH & YMMV, > > HAND! > > chal_ping wrote: > > > > oracle-lHi, grurus: > > This is a production database 8.1.7.2 on aix 4.3.3, there are 17 > instances running on the same box. > > I shutdown immediate the database and it hangs.After wait for one > hour, i do a shutdown abort. When i startup again, it failed to open the > database , just hangs at this stage like: > > Sun Jun 16 09:36:40 2002 > > SMON: enabling cache recovery > > SMON: enabling tx recovery > > And the sql*plus window hangs at : database mounted, but never > showed open. > > From another shell prompt, i sqlplus internal and query the > instance, it showed instance open in read write state! > > But from remote node via listener, client process showed 0134: > oracle not available. > > I once met such kind of questions on sun solaris, it is because > of solaris bug.But never heard of this kind on AIX. Oracle support suggest > reboot the server, but as there is 16 other instance on it, it is not the > solution. > > Can anyone help? > > Great thanks. > > > > -- > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: > INET: Rajesh.Rao_at_jpmchase.com > > 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). -- Danisment Gazi Unal http://www.ubTools.com -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: INET: Rajesh.Rao_at_jpmchase.com 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). -- Danisment Gazi Unal http://www.ubTools.com -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: INET: Rajesh.Rao_at_jpmchase.com 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).Received on Thu Jun 20 2002 - 10:18:29 CDT
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