Re: Higher Read response in 19C
- From: Mladen Gogala <gogala.mladen@xxxxxxxxx>
- To: oracle-l@xxxxxxxxxxxxx
- Date: Sat, 17 Sep 2022 11:09:46 -0400
On 9/17/22 06:01, Lok P wrote:
Hello Listers, Post 19C migration we are seeing the response time of
'direct path read temp' has been bumped up from ~1.6ms to ~36ms. So we
have many queries doing temp read while performing hash join
performing slow. Also we have observed the amount of tempspill remains
the same as it was before for those queries. We had a PGA size 40GB of
PGA on 11g , on 19c we made it 60GB. Wanted to understand the cause of
this high temp read response and how to fix.
Have you considered doing strace and "perf top"? That will show you what
calls are you waiting for. The difference is too large for a minor
algorithm change. You may be paging and allocating extra memory which
may be problematic. Hopefully, you're not using automatic memory on Exadata?
--
Mladen Gogala
Database Consultant
Tel: (347) 321-1217
https://dbwhisperer.wordpress.com
Other related posts:
