MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII;
 format=flowed
Content-Transfer-Encoding: 7bit
Date: Wed, 23 Sep 2020 17:17:04 +0900
From: Katsuragi Yuta <btkatsuragiyu@oss.nttdata.com>
To: Julien Rouhaud <rjuju123@gmail.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>, legrand legrand
 <legrand_legrand@hotmail.com>
Subject: Re: [PATCH] Add features to pg_stat_statements
In-Reply-To: 
 <CAOBaU_bV8K29DEimA_+VNHd=0kPghxzQpepyhn=WAzJh6CL7ag@mail.gmail.com>
References: <0d9f1107772cf5c3f954e985464c7298@oss.nttdata.com>
 <CAOBaU_bYknq5in+fp9m8ufQPGq+O82Sk-UKPjfz9P4fFUBA36Q@mail.gmail.com>
 <193879cdb9f6e14060bde2172f8399c9@oss.nttdata.com>
 <CAOBaU_bV8K29DEimA_+VNHd=0kPghxzQpepyhn=WAzJh6CL7ag@mail.gmail.com>
Message-ID: <8ad65061e81ad622cb4a4b6fbbe25646@oss.nttdata.com>
User-Agent: Roundcube Webmail/1.1.9
Precedence: bulk

On 2020-09-23 16:01, Julien Rouhaud wrote:
>> Not only providing a view but also logging evictions
>> along with the number of evicted entries might be a choice.
>> This idea is from legrand legrand [1].
> 
> +1.  I'm wondering if logging each evicted entry, with its queryid,
> would help to estimate the actual size of the normalised queries set.

I agree with the estimation of the actual size of the
query set is important.
It looks difficult to estimate the actual size of the
query set from queryid because queryid is a 64bit hash value.

Regards,
Katsuragi Yuta