From: Jean-David Beyer <jeandavid8@verizon.net>
To: pgsql-sql@postgresql.org
Subject: Re: Block size with pg_dump?
Date: Mon, 27 Aug 2007 08:28:25 -0400
Message-ID: <46D2C369.7040806@verizon.net> (raw)
In-Reply-To: <200708270249.l7R2nfX00882@momjian.us>
References: <200708270249.l7R2nfX00882@momjian.us>
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Bruce Momjian wrote:
> Erik Jones wrote:
>>>>> On the way back, likewise I could pipe the tape through dd before
>>>>> giving it
>>>>> to pg_restore.
>>>>>
>>>>> Does pg_dump care what blocksize it gets? If so, what is it?
>>>> I assume you could pipe pg_dump into dd and specify the block size in
>>>> dd.
>>>>
>>> Of course on the way out I can do that.
>>>
>>> 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?
- --
.~. Jean-David Beyer Registered Linux User 85642.
/V\ PGP-Key: 9A2FC99A Registered Machine 241939.
/( )\ Shrewsbury, New Jersey http://counter.li.org
^^-^^ 08:25:01 up 18 days, 11:47, 2 users, load average: 4.34, 4.31, 4.27
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To: pgsql-sql@postgresql.org
Cc: jeandavid8@verizon.net
Subject: Re: Block size with pg_dump?
In-Reply-To: <46D2C369.7040806@verizon.net>
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