From: Tom Lane <tgl@sss.pgh.pa.us>
To: Michael Paquier <michael@paquier.xyz>
cc: Alexander Lakhin <exclusion@gmail.com>, pgsql-hackers@postgresql.org
Subject: Re: Fix typos and inconsistencies for HEAD (take 7)
In-reply-to: <20190722010543.GB1757@paquier.xyz>
References: <dff75442-2468-f74f-568c-6006e141062f@gmail.com>
 <20190722010543.GB1757@paquier.xyz>
Comments: In-reply-to Michael Paquier <michael@paquier.xyz>
	message dated "Mon, 22 Jul 2019 10:05:50 +0900"
MIME-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-ID: <28138.1563768879.1@sss.pgh.pa.us>
Content-Transfer-Encoding: 8bit
Date: Mon, 22 Jul 2019 00:14:39 -0400
Message-ID: <28139.1563768879@sss.pgh.pa.us>
Precedence: bulk

Michael Paquier <michael@paquier.xyz> writes:
> On Sun, Jul 21, 2019 at 08:28:53AM +0300, Alexander Lakhin wrote:
>> And another finding is related to the sleep effective resolution. `man 7
>> time` says "Since kernel 2.6.13, the HZ value is a kernel configuration 
>> parameter  and  can  be 100, 250 (the default) ...", so the 10
>> milliseconds is not the most common effective resolution nowadays.
>> I propose the corresponding patch for pgsleep.c, but we have a similar
>> statement in doc/.../config.sgml. I think It should be fixed too.

> Fixing both places sounds adapted to me.  An alternative we could use
> here is just to say something like that:
> The effective resolution is only 1/HZ, which can be configured with
> kernel parameter (see man 7 time), and is 4 milliseconds by
> default.

Whatever we say here is going to be a lie on some platforms.

Probably best just to say that the sleep resolution is platform-dependent
and leave it at that.

			regards, tom lane