Re: How to gracefully keep my specific index in memory ?

Thanks Laurenz Albe for reply.

Unfortunately this index is only frequently used during a certain period of time(such as 9:30am - 12:00am) .I usually encounter slow load of this index during some other time.
Then it seems to me the only answer for this case would be the pgprewarm and pg_cron ?


------------------ Original ------------------
From: "Laurenz Albe"<laurenz(dot)albe(at)cybertec(dot)at>;
Date: Mon, Aug 12, 2019 08:24 PM
To: "James(王旭)"<wangxu(at)gu360(dot)com>; "pgsql-general"<pgsql-general(at)postgresql(dot)org>;

Subject: Re: How to gracefully keep my specific index in memory ?

James(王旭) wrote:
> As the title,How to keep a specific index in memory gracefully?
>
> After some statistical query, I can determine that not all indexes can be fit into memory,
> but one of the most frequently used indexes(say idx_xyz) can be definitely fit into
> memory(specifically ,[the size of idx_xyz]=20% x [memory size]).
>
> I know there's pgprewarm, but I feel with pgprewarm I can't keep things under control, e.g. no realtime monitor, being squeezed out of memory ,.etc.
>
> Is it possible that I can simply do something like "select idx_xyz into xxx" and keep the specific index in memory forever?

If the indexes are frequently used, they should remain cached anyway.

Yours,
Laurenz Albe
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