RE: Performance Question - High I/O per Insert
- From: Graeme.Farmer@xxxxxxxxxx
- To: mstrickland@xxxxxxxxxxxxx
- Date: Sun, 10 Oct 2004 22:51:53 +1000
Any triggers on the table that refer to data found in the current week's
partition? This is a classic cause of high I/O per insert.
Graeme
oracle-l-bounce@xxxxxxxxxxxxx wrote on 29/09/2004 05:27:28 AM:
> This is a follow-up to a question I posed earlier, but I have more info.
> A SQL*Loader conventional path load inserts rows into a table
> partitioned by week. On the first day of a new week, the load runs as
> efficiently as expected, but as the week goes on, the load goes more and
> more slowly. There is a single local index on each partition and the
> blevel is 2. I'm scratching my head. I realize I'm not providing much
> info, but can anyone tell me why loading into a partition might get
> slower as the partition fills? Thx!
>
>
> Mark Strickland
>
>
>
> ________________________________
>
> From: Mark Strickland
> Sent: Wednesday, September 22, 2004 12:42 PM
> To: oracle-l@xxxxxxxxxxxxx
> Subject: Performance Question - High I/O per Insert
>
>
>
> I'm trying to understand why I'm seeing a high number of I/Os for
> inserts. Inserts are through SQL*Loader conventional patch. Average
> row length is 129 bytes, no longs or blobs. The table has five indexes
> and each index has a blevel of 2. According to v$sqlarea, each insert
> uses 650 logical I/Os, 69 physical I/Os. I would expect fewer than 20
> I/Os per insert. There are db file sequential read waits on the data
> files that make up the index tablespace. That file system also contains
> the archived logs. Not surprised at the contention. Can someone point
> me in the right direction to understand this? Thx.
>
>
>
> Mark Strickland
>
> Drugstore.com
>
> Seattle, WA
>
>
> --
> //www.freelists.org/webpage/oracle-l
--
This transmission is for the intended addressee only and is confidential
information. If you have received this transmission in error, please notify the
sender and delete the transmission. The contents of this e-mail are the opinion
of the writer only and are not endorsed by the Mincom Group of companies unless
expressly stated otherwise.
--
//www.freelists.org/webpage/oracle-l
Other related posts:
