Horton

Re: auto-sizing wal_buffers

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Jaime Casanova <jaime@2ndquadrant.com>
Cc: Greg Smith <greg@2ndquadrant.com>, Fujii Masao <masao.fujii@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, Magnus Hagander <magnus@hagander.net>, pgsql-hackers@postgresql.org
Date: 2011-01-22T14:54:53Z
Lists: pgsql-hackers 
On Sat, Jan 22, 2011 at 1:30 AM, Jaime Casanova <jaime@2ndquadrant.com> wrote:
> why is this better than using XLOG_BUFFER_MIN? (the same for the 8
> buffers assigned just above of it)
>
> +       else if (XLOGbuffers < 4)
> +               XLOGbuffers = 4;

Oh, good point.  Woops.

> also this
> +       Assert(XLOGbuffers > 0);
> maybe should be
>        Assert(XLOGbuffers >= XLOG_BUFFER_MIN);

I think that's slightly less clear about the point of the assertion,
which is to make sure we're at least allocating something.

> while you move the code, why didn't you keep this comment?
> -                                       /*
> -                                        * Use int64 arithmetic to avoid overflows in units
> -                                        * conversion.
> -                                        */

Because I suck.  Will fix.

Thanks for the fast and detailed review.

-- 
Robert Haas
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