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To: Robert Haas <robertmhaas@gmail.com>
cc: Greg Smith <greg@2ndquadrant.com>, Fujii Masao <masao.fujii@gmail.com>,
	Magnus Hagander <magnus@hagander.net>, pgsql-hackers@postgresql.org
Subject: Re: auto-sizing wal_buffers 
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Sat, 22 Jan 2011 21:52:18 -0500"
Date: Sat, 22 Jan 2011 22:12:16 -0500
Message-ID: <1334.1295752336@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Robert Haas <robertmhaas@gmail.com> writes:
> On Sat, Jan 22, 2011 at 9:42 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> It does strike me that we could provide SetConfigOptionInt,
>> SetConfigOptionBool, and SetConfigOptionReal for the benefit of callers
>> who'd prefer to pass values in those formats.  They'd still do sprintf
>> internally, but this would make the call sites a bit cleaner.

> Why do we need to double the conversion in the first place?

Because most of the processing in set_config_option is independent of
the type of the GUC variable.  Maybe it could be refactored, but I don't
think it would come out prettier, nor faster.  Again, the important code
paths are starting from string values anyway --- I don't think we should
contort the design of guc.c to serve a small minority of callers at the
expense of complicating the normal cases.

			regards, tom lane