On 2/12/19 7:33 AM, Tsunakawa, Takayuki wrote:
> ...
>
> This problem was uncovered while evaluating partitioning performance.
> When the application PREPAREs a statement once and then
> EXECUTE-COMMIT repeatedly, the server creates a generic plan on the
> 6th EXECUTE. Unfortunately, creation of the generic plan of
> UPDATE/DELETE currently accesses all partitions of the target table
> (this itself needs improvement), expanding the LOCALLOCK hash table.
> As a result, 7th and later EXECUTEs get slower.
>
> Imai-san confirmed performance improvement with this patch:
>
> https://commitfest.postgresql.org/22/1993/
>
Can you quantify the effects? That is, how much slower/faster does it get?
regards
--
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