Re: BufFileWrite across MAX_PHYSICAL_FILESIZE boundary

From: Bruce Momjian <bruce(at)momjian(dot)us>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Kurt Harriman <kharriman(at)greenplum(dot)com>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: BufFileWrite across MAX_PHYSICAL_FILESIZE boundary
Date: 2007-05-17 01:09:50
Message-ID: 200705170109.l4H19oJ06122@momjian.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers


This has been saved for the 8.4 release:

http://momjian.postgresql.org/cgi-bin/pgpatches_hold

---------------------------------------------------------------------------

Tom Lane wrote:
> "Kurt Harriman" <kharriman(at)greenplum(dot)com> writes:
> > Just noticed buffile.c:292 doesn't look quite right where
> > BufFileDumpBuffer calls FileWrite:
> > bytestowrite = FileWrite(thisfile, file->buffer, bytestowrite);
> > It looks as though it would write the same data each time the
> > loop is iterated. Would this be better?
> > bytestowrite = FileWrite(thisfile, file->buffer + wpos, bytestowrite);
>
> Yeah, I think you're right. We've probably not seen this because in
> most usages the buffer is always block-aligned, but it looks possible
> for tuplestore.c to get out of alignment if its concurrent write/read
> feature is exercised just so. Do you want to try demonstrating the bug
> with a smaller-than-normal setting of MAX_PHYSICAL_FILESIZE?
>
> regards, tom lane
>
> ---------------------------(end of broadcast)---------------------------
> TIP 5: don't forget to increase your free space map settings

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Marc G. Fournier 2007-05-17 01:34:50 Re: Lack of urgency in 8.3 reviewing
Previous Message Bruce Momjian 2007-05-17 01:07:31 Re: Implemented current_query