Re: Simple Insert - very slow

From: Sanjay Mishra <"Sanjay>
Date: Fri, 17 May 2019 21:32:10 +0000 (UTC)
Message-ID: <>

Thanks for the update. Based on the Obj Id with trace on the Insert process, it is Table itself reported. This table is recently exported and imported and Index was only created less than a month back. Surprisingly not able to understand as to why it is doing cell single block physical read to the table. I will also check your link and do more troubleshooting  TxSanjay

    On Friday, May 17, 2019, 10:29:45 AM PDT, Andy Sayer <> wrote:  

 First step would be to see which object is responsible for all the IO, in my experience it’s usually down to one index. Have a look at for how I’ve tackled this before. It might be you’ve got a “bad index” or it might be that you’ve got an okay index that turned “bad”.  We had a case where an index exploded and was purely ITL for the first few thousands leaf blocks, we reset the sequence (told to by support) which meant that all our inserts had to scan those few thousand leaf blocks to insert one row.  First step is identifying the object
On Fri, 17 May 2019 at 16:47, Sanjay Mishra <> wrote:

Hi All
We have a table with around a billion rows with one Primary Key. Number of columns in the table  are fewer than 10 and all are numbers data type. Application is doing few million inserts but running very slow. It is Exadata with two node and 10CPU and good SGA (bufer Cache 10G). Waits are coming heavily only for "cell single block physical read"  for Insert process.  While doing SQL Monitor shows it is doing high IO like more than 100G for simple Insert. Oracle version is 12.2. Any suggestions as what can be the reason for this wait event in this scenario. TIASanjay   

Received on Fri May 17 2019 - 23:32:10 CEST

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