On Thu, 27 May 2021 at 11:32 AM, tsunakawa.ta...@fujitsu.com < tsunakawa.ta...@fujitsu.com> wrote:
> From: Dilip Kumar <dilipbal...@gmail.com> > > I think some other cause of contention on relation extension locks are > > 1. CTAS is using a buffer strategy and due to that, it might need to > > evict out the buffer frequently for getting the new block in. Maybe > > we can identify by turning off the buffer strategy for CTAS and > > increasing the shared buffer so that data fits in memory. > > Yes, both Bhrath-san (on a rich-man's machine) and I (on a poor-man's VM) > saw that it's effective. I think we should remove this shackle from CTAS. > > The question is why CTAS chose to use BULKWRITE strategy in the past. We > need to know that to make a better decision. Basically you are creating a new table and loading data to it and that means you will be less likely to access those data soon so for such thing spoiling buffer cache may not be a good idea. I was just suggesting only for experiments for identifying the root cause. > -- Regards, Dilip Kumar EnterpriseDB: http://www.enterprisedb.com
