Subject: Re: Improve logging when using Huge Pages
To: Justin Pryzby <pryzby@telsasoft.com>
Cc: "Shinoda, Noriyoshi (PN Japan FSIP)" <noriyoshi.shinoda@hpe.com>,
 pgsql-hackers@postgresql.org, Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
 "rjuju123@gmail.com" <rjuju123@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
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From: Fujii Masao <masao.fujii@oss.nttdata.com>
Message-ID: <b202326e-0d2c-c4f1-6f50-cb2b9e22e887@oss.nttdata.com>
Date: Fri, 17 Sep 2021 00:12:39 +0900
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On 2021/09/07 22:16, Justin Pryzby wrote:
> On Tue, Sep 07, 2021 at 07:12:36PM +0900, Fujii Masao wrote:
>> One big concern about the patch is that log message is always reported
>> when shared memory fails to be allocated with huge pages enabled
>> when huge_pages=try. Since huge_pages=try is the default setting,
>> many users would see this new log message whenever they start
>> the server. Those who don't need huge pages but just use the default
>> setting might think that such log messages would be noisy.
> 
> I don't see this as any issue.  We're only talking about a single message on
> each restart, which would be added in a major release.

I was afraid that logging the message like "could not ..." every time
when the server starts up would surprise users unnecessarily.
Because the message sounds like it reports a server error.
So it might be good idea to change the message to something like
"disabling huge pages" to avoid such surprise.

>  If it's a problem, the
> message could be a NOTICE or INFO, and it won't be shown by default.

That's an idea, but neither NOTICE nor INFO are suitable for
this kind of message....

Regards,

-- 
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION