Re: rman backup slow even after patching it

From: <niall.litchfield_at_gmail.com>
Date: Mon, 22 Aug 2022 16:27:52 +0100
Message-ID: <CABe10sZrzYuTY+ZswE3rydP1Yn_e9Od_1nYf5xFYFBTSHdqBOg_at_mail.gmail.com>



What does "slow" mean in this context?

On Mon, Aug 15, 2022 at 6:37 PM Beckstrom, Jeffrey <jbeckstrom_at_gcrta.org> wrote:

> In 19.14, rman backup significantly slower than in 11g. This morning I put
> on some RMAN patches to no effect. In the rman trace file from a running
> backup I see:
>
>
>
> Adjusting buffer count to honor available PGA; old bufcnt: 4, new bufcnt:
> 2, pga_agg_limit: 0, pga_agg_target: 0, pga_agg_used: 892876434,
> pga_available: 0
>
> Adjusting buffer count to honor available PGA; old bufcnt: 4, new bufcnt:
> 2, pga_agg_limit: 0, pga_agg_target: 0, pga_agg_used: 892876434,
> pga_available: 0
>
> Adjusting buffer count to honor available PGA; old bufcnt: 5, new bufcnt:
> 2, pga_agg_limit: 0, pga_agg_target: 0, pga_agg_used: 892876434,
> pga_available: 0
>
> Adjusting buffer count to honor available PGA; old bufcnt: 6, new bufcnt:
> 2, pga_agg_limit: 0, pga_agg_target: 0, pga_agg_used: 892876434,
> pga_available: 0
>
> Adjusting buffer count to honor available PGA; old bufcnt: 4, new bufcnt:
> 2, pga_agg_limit: 0, pga_agg_target: 0, pga_agg_used: 892876434,
> pga_available: 0
>
> Adjusting buffer count to honor available PGA; old bufcnt: 5, new bufcnt:
> 2, pga_agg_limit: 0, pga_agg_target: 0, pga_agg_used: 892876434,
> pga_available: 0
>
> Adjusting buffer count to honor available PGA; old bufcnt: 8, new bufcnt:
> 2, pga_agg_limit: 0, pga_agg_target: 0, pga_agg_used: 892876434,
> pga_available: 0
>
> Adjusting buffer count to honor available PGA; old bufcnt: 16, new bufcnt:
> 2, pga_agg_limit: 0, pga_agg_target: 0, pga_agg_used: 892876434,
> pga_available: 0
>
> Backup envisage an unusual situation due to PGA memory availability: we
> are using only 2 read threads (instead of 9) for the current backup session
>
> Adjusting buffer count to honor available PGA; old bufcnt: 4, new bufcnt:
> 2, pga_agg_limit: 0, pga_agg_target: 0, pga_agg_used: 913692181,
> pga_available: 0
>
>
>
>
>
> Pga_aggregate targe is set at the cdb to a value. At the pdb level it is 0.
>
> Pga_aggregate_limit is not set anywhere.
>
>
>
> Do I need to set the pga_aggregate limit?
>
>
>
> Do I need to set both parameters at the PDB level?
>
>
>
> Jeffrey Beckstrom
>
> Greater Cleveland Regional Transit Authority
>
> 1240 W. 6th Street
>
> Cleveland, Ohio 44113
>
>
>

-- 
Niall Litchfield
Oracle DBA
http://www.orawin.info

--
http://www.freelists.org/webpage/oracle-l
Received on Mon Aug 22 2022 - 17:27:52 CEST

Original text of this message