Re: FW: huge SubtransSLRU and SubtransBuffer wait_event

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Hi Alvaro ,
 looks like  Xact slru buffer use a different way to control size, do we need to increase Xact and how to increase that ?   we plan to increase to 20 times size of existing buffers,  any side impact to 20 times increase these subtrans ? 
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Thanks,

James 

Alvaro Herrera <alvherre@xxxxxxxxxxxxxx> 於 2024年3月1日週五 下午3:35寫道:
On 2024-Mar-01, James Pang wrote:

> one question:
>      we need to increase all SLRU buffers together , MULTIXACT, XACT,
> Subtrans, COMMIT TS ,  for example, got all of them doubled based on
> existing size ?

No need.

> or only increase Subtrans , or Subtrans and multixact ?

Just increase the sizes for the ones that are causing you pain. You can
have a look at pg_stat_slru for some metrics that might be useful in
determining which are those.

--
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/

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