Re: Memory Alignment in Postgres - Mailing list pgsql-hackers

From Robert Haas
Subject Re: Memory Alignment in Postgres
Date
Msg-id CA+Tgmob_dNSeYY2EYP-3bivysY4_5T+zCokLWwLm4nuc_rDjAg@mail.gmail.com
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In response to Re: Memory Alignment in Postgres  (Bruce Momjian <bruce@momjian.us>)
List pgsql-hackers
On Wed, Sep 10, 2014 at 4:29 PM, Bruce Momjian <bruce@momjian.us> wrote:
> On Wed, Sep 10, 2014 at 11:43:52AM -0400, Robert Haas wrote:
>> But there are a couple of obvious problems with this idea, too, such as:
>>
>> 1. It's really complicated and a ton of work.
>> 2. It would break pg_upgrade pretty darn badly unless we employed some
>> even-more-complex strategy to mitigate that.
>> 3. The savings might not be enough to justify the effort.
>>
>> It might be interesting for someone to develop a tool measuring the
>> number of bytes of alignment padding we lose per tuple or per page and
>> gather some statistics on it on various databases.  That would give us
>> some sense as to the possible savings.
>
> And will we ever implement a logical attribute system so we can reorder
> the stored attribtes to minimize wasted space?

You forgot to attach the patch.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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