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Date: Tue, 2 Feb 2010 13:14:40 -0500
Message-ID: <603c8f071002021014h4b489f44s9014377e1b38dbc7@mail.gmail.com>
Subject: Re: [HACKERS] Re: Faster CREATE DATABASE by delaying fsync (was 8.4.1
	ubuntu karmic slow createdb)
From: Robert Haas <robertmhaas@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>, Greg Stark <gsstark@mit.edu>,
	pgsql-hackers@postgresql.org, pgsql-performance@postgresql.org,
	Michael Clemmons <glassresistor@gmail.com>,
	Hannu Krosing <hannu@2ndquadrant.com>,
	Scott Marlowe <scott.marlowe@gmail.com>
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On Tue, Feb 2, 2010 at 12:50 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Andres Freund <andres@anarazel.de> writes:
>> On Tuesday 02 February 2010 18:36:12 Robert Haas wrote:
>>> I took a look at this patch today and I agree with Tom that
>>> pg_fsync_start() is a very confusing name. =A0I don't know what the
>>> right name is, but this doesn't fsync so I don't think it shuld have
>>> fsync in the name. =A0Maybe something like pg_advise_abandon() or
>>> pg_abandon_cache(). =A0The current name is really wishful thinking:
>>> you're hoping that it will make the kernel start the fsync, but it
>>> might not. =A0I think pg_start_data_flush() is similarly optimistic.
>
>> What about: pg_fsync_prepare().
>
> prepare_for_fsync()?

It still seems mis-descriptive to me.  Couldn't the same routine be
used simply to abandon undirtied data that we no longer care about
caching?

...Robert