From: Bruce Momjian <bruce@momjian.us>
Message-Id: <200708271233.l7RCXP003515@momjian.us>
Subject: Re: Block size with pg_dump?
In-Reply-To: <46D2C369.7040806@verizon.net>
To: Jean-David Beyer <jeandavid8@verizon.net>
Date: Mon, 27 Aug 2007 08:33:25 -0400 (EDT)
CC: pgsql-sql@postgresql.org
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Jean-David Beyer wrote:
> >>> The main question is, If I present pg_restore with a 65536-byte  
> >>> blocksize
> >>> and it is expecting, e.g., 1024-bytes, will the rest of each block get
> >>> skipped? I.e., do I have to use dd on the way back too? And if so,  
> >>> what
> >>> should the blocksize be?
> >> Postgres (by default) uses 8K blocks.
> > 
> > That is true of the internal storage, but not of pg_dump's output
> > because it is using libpq to pull rows and output them in a stream,
> > meaning there is no blocking in pg_dumps output itself.
> > 
> Is that true for both input and output (i.e., pg_restore and pg_dump)?
> I.e., can I use dd to write 65536-byte blocks to tape, and then do nothing
> on running pg_restore? I.e., that pg_restore will accept any block size I
> choose to offer it?

Yes.

-- 
  Bruce Momjian  <bruce@momjian.us>          http://momjian.us
  EnterpriseDB                               http://www.enterprisedb.com

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