RE: OLTP compression slow update

  • From: <Christopher.Taylor2@xxxxxxxxxxxx>
  • To: <mdinh235@xxxxxxxxx>, <rjamya@xxxxxxxxx>
  • Date: Thu, 27 Dec 2012 13:40:45 -0600

I know I'm late to the party so this might have been covered.  Is this a single 
session update statement or multiple sessions?

I was wondering about ITL waits if multiple sessions - but if it's a single 
session then I figure ITL waits shouldn't be an issue unless the free space in 
each block is really, really, low.

While you're testing, grab some AWR reports (change your collection interval 
for 5-10 minutes from default 60 minutes) and check your wait events.  (Yes, I 
know I'm probably preaching to the choir here - but just in case...)

Chris

-----Original Message-----
From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On 
Behalf Of Michael Dinh
Sent: Thursday, December 27, 2012 12:51 PM
To: rjamya@xxxxxxxxx
Cc: oracle-l
Subject: Re: OLTP compression slow update

Thanks all for the ressponse.
Still testing and will share results.

-Michael.

On Thu, Dec 27, 2012 at 4:52 AM, rjamya <rjamya@xxxxxxxxx> wrote:

> I saw this first in early 10g versions of plain vanilla compression 
> (not fancy oltp etc). We  were analyzing http/smtp logs collected 
> company-wide, Initially we had daily partitions. since it started 
> getting large quickly (we had open web at that time), I introduced 
> partition compression, it worked like magic. When updates (due to 
> occasional re-loads, corrections, ranking etc) to compressed 
> partitions took long, we redesigned our strategy. Kept 7 days worth of 
> parttions uncompressed, and everything older was compressed. That 
> worked out well in the end. I guess the update issue on compressed 
> data still needs work then :) Raj
>
>
> --
> //www.freelists.org/webpage/oracle-l
>
>
>


--
//www.freelists.org/webpage/oracle-l


--
//www.freelists.org/webpage/oracle-l


Other related posts: