Re: Running PostgreSQL as fast as possible no matter the consequences

От: Bruce Momjian
Тема: Re: Running PostgreSQL as fast as possible no matter the consequences
Дата: ,
Msg-id: 201101260132.p0Q1Wjb09621@momjian.us
(см: обсуждение, исходный текст)
Ответ на: Re: Running PostgreSQL as fast as possible no matter the consequences  (Robert Haas)
Ответы: Re: Running PostgreSQL as fast as possible no matter the consequences  (Jeff Janes)
Список: pgsql-performance

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Running PostgreSQL as fast as possible no matter the consequences  (A B, )
 Re: Running PostgreSQL as fast as possible no matter the consequences  (Thom Brown, )
  Re: Running PostgreSQL as fast as possible no matter the consequences  (Thom Brown, )
  Re: Running PostgreSQL as fast as possible no matter the consequences  (A B, )
 Re: Running PostgreSQL as fast as possible no matter the consequences  (Guillaume Cottenceau, )
  Re: Running PostgreSQL as fast as possible no matter the consequences  (Marti Raudsepp, )
   Re: Running PostgreSQL as fast as possible no matter the consequences  (Guillaume Cottenceau, )
 Re: Running PostgreSQL as fast as possible no matter the consequences  (Szymon Guz, )
  Re: Running PostgreSQL as fast as possible no matter the consequences  (A B, )
   Re: Running PostgreSQL as fast as possible no matter the consequences  (Marti Raudsepp, )
    Re: Running PostgreSQL as fast as possible no matter the consequences  (Thom Brown, )
    Re: Running PostgreSQL as fast as possible no matter the consequences  (Guillaume Cottenceau, )
     Re: Running PostgreSQL as fast as possible no matter the consequences  (Jon Nelson, )
      Re: Running PostgreSQL as fast as possible no matter the consequences  (Robert Haas, )
       Re: Running PostgreSQL as fast as possible no matter the consequences  (Andy Colson, )
        Re: Running PostgreSQL as fast as possible no matter the consequences  (Robert Haas, )
   Re: Running PostgreSQL as fast as possible no matter the consequences  (Craig Ringer, )
   Re: Running PostgreSQL as fast as possible no matter the consequences  ("Lello, Nick", )
    Re: Running PostgreSQL as fast as possible no matter the consequences  (Dimitri Fontaine, )
    Re: Running PostgreSQL as fast as possible no matter the consequences  (Klaus Ita, )
 Re: Running PostgreSQL as fast as possible no matter the consequences  (Craig Ringer, )
  Re: Running PostgreSQL as fast as possible no matter the consequences  (A B, )
 Re: Running PostgreSQL as fast as possible no matter the consequences  (Devrim GÜNDÜZ, )
  Re: Running PostgreSQL as fast as possible no matter the consequences  (Mladen Gogala, )
 Re: Running PostgreSQL as fast as possible no matter the consequences  (Chris Browne, )
  Re: Running PostgreSQL as fast as possible no matter the consequences  (Bruce Momjian, )
   Re: Running PostgreSQL as fast as possible no matter the consequences  (Fabrízio de Royes Mello, )
   Re: Running PostgreSQL as fast as possible no matter the consequences  (Robert Haas, )
    Re: Running PostgreSQL as fast as possible no matter the consequences  (Bruce Momjian, )
     Re: Running PostgreSQL as fast as possible no matter the consequences  (Jeff Janes, )
      Re: Running PostgreSQL as fast as possible no matter the consequences  (Bruce Momjian, )

Robert Haas wrote:
> On Wed, Jan 19, 2011 at 12:07 PM, Bruce Momjian <> wrote:
> > Chris Browne wrote:
> >>  (A B) writes:
> >> > If you just wanted PostgreSQL to go as fast as possible WITHOUT any
> >> > care for your data (you accept 100% dataloss and datacorruption if any
> >> > error should occur), what settings should you use then?
> >>
> >> Use /dev/null. ?It is web scale, and there are good tutorials.
> >>
> >> But seriously, there *are* cases where "blind speed" is of use. ?When
> >> loading data into a fresh database is a good time for this; if things
> >> fall over, it may be pretty acceptable to start "from scratch" with
> >> mkfs/initdb.
> >>
> >> I'd:
> >> - turn off fsync
> >> - turn off synchronous commit
> >> - put as much as possible onto Ramdisk/tmpfs/similar as possible
> >
> > FYI, we do have a documentation section about how to configure Postgres
> > for improved performance if you don't care about durability:
> >
> > ? ? ? ?http://developer.postgresql.org/pgdocs/postgres/non-durability.html
>
> This sentence looks to me like it should be removed, or perhaps clarified:
>
>     This does affect database crash transaction durability.

Uh, doesn't it affect database crash transaction durability?  I have
applied the attached patch to clarify things.  Thanks.

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

  + It's impossible for everything to be true. +
diff --git a/doc/src/sgml/perform.sgml b/doc/src/sgml/perform.sgml
index 2699828..fb55598 100644
*** a/doc/src/sgml/perform.sgml
--- b/doc/src/sgml/perform.sgml
*************** SELECT * FROM x, y, a, b, c WHERE someth
*** 1159,1165 ****
        <para>
         Turn off <xref linkend="guc-synchronous-commit">;  there might be no
         need to write the <acronym>WAL</acronym> to disk on every
!        commit.  This does affect database crash transaction durability.
        </para>
       </listitem>
      </itemizedlist>
--- 1159,1165 ----
        <para>
         Turn off <xref linkend="guc-synchronous-commit">;  there might be no
         need to write the <acronym>WAL</acronym> to disk on every
!        commit.  This can cause transaction loss after a server crash.
        </para>
       </listitem>
      </itemizedlist>


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