I don't know Oracle Corp. has published Deferred Transaction Rollback term externally. But, I know this term is available.
Deferred Transaction Rollback was introduced in 7.3. It enables database to be opened after roll forward is completed. The rollback of any uncomitted tx will be done by SMON/user process after database is opened. In other words, there is no rollback operation in Deferred Transaction Rollback. It's just a roll forward operation.
In Oracle8i, Oracle corp. has renamed Parallel Transaction Recovery term to Fast Start Parallel Rollback term. If SMON determines that tx has 100+ rollback blocks, SMON uses parallel query slaves to complete rollback.
I think we are saying same thing.
regards...
[EMAIL PROTECTED] wrote:
>> 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 <[EMAIL PROTECTED]>
(ubTools)" cc:
<dunal@ubTool Subject: Re: production database on aix won't be open, help
s.com>
Sent by:
root@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...
[EMAIL PROTECTED] 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 <[EMAIL PROTECTED]>
> (ubTools)" cc:
> <dunal@ubTool Subject: Re: production
database on aix won't be open, help
> s.com>
> Sent by:
> root@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.
>
> [EMAIL PROTECTED] 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 <[EMAIL PROTECTED]>
> > <charliem@mwh cc:
> > .com> Subject: Re: production
> database on aix won't be open, help
> > Sent by:
> > root@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: [EMAIL PROTECTED]
> >
> > 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: [EMAIL PROTECTED] (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: [EMAIL PROTECTED]
>
> 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: [EMAIL PROTECTED] (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.comYes,
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...
[EMAIL PROTECTED] wrote:
Yup. FYI, this is what Metalink says:A
final new feature forspecifying bounded recovery time
is
the use of fast-startparallel 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. InOracle8i, 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_TRANSACTIONSviews.
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 beginsparallel 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 <[EMAIL PROTECTED]>
(ubTools)" cc:
<dunal@ubTool Subject: Re: production
database on aix won't be open, help
s.com>
Sent by:
root@fatcity.
comJune 19, 2002
04:27 PM
Please
respond to
ORACLE-LHello 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.[EMAIL PROTECTED] 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 <[EMAIL PROTECTED]>
> <charliem@mwh cc:
> .com> Subject: Re: productiondatabase on aix won't be open, help
> Sent by:
> root@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: [EMAIL PROTECTED]
>
> 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: [EMAIL PROTECTED] (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: [EMAIL PROTECTED]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: [EMAIL PROTECTED] (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: [EMAIL PROTECTED]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: [EMAIL PROTECTED] (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
