Re: Performance degradation of REFRESH MATERIALIZED VIEW

On 5/11/21 12:58 PM, Bharath Rupireddy wrote:
> On Tue, May 11, 2021 at 2:34 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>> I think the approach proposed by Andres eliminates the extra vmbuffer
>> reads as much as possible. But even with the patch, there still is 5%
>> degradation (and there is no way to disable inserting frozen tuples at
>> matview refresh). Which could be a problem for some users. I think
>> it’s hard to completely eliminate the overhead so we might need to
>> consider another approach like having matview refresh use
>> heap_multi_insert() instead of heap_insert().
> 
> I may not have understood what's being discussed here completely, but
> if you want to use multi inserts for refresh matview code, maybe the
> "New Table Access Methods for Multi and Single Inserts" patches at
> [1], can help.
> 

Maybe, but I think the main question is what to do for v14, so the 
uncommitted patch is kinda irrelevant.


regards

-- 
Tomas Vondra
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