Re: Caching by Postgres

From: PFC
Subject: Re: Caching by Postgres
Date: ,
Msg-id: op.svzh7sqdth1vuj@localhost
(view: Whole thread, Raw)
In response to: Re: Caching by Postgres  (William Yu)
Responses: Re: Caching by Postgres  (Josh Berkus)
Re: Caching by Postgres  (Gavin Sherry)
List: pgsql-performance

Tree view

Caching by Postgres  (gokulnathbabu manoharan, )
 Re: Caching by Postgres  (John A Meinel, )
  Re: Caching by Postgres  (Josh Berkus, )
 Re: Caching by Postgres  (Bruno Wolff III, )
 Re: Caching by Postgres  (Frank Wiles, )
  Re: Caching by Postgres  (Donald Courtney, )
   Re: Caching by Postgres  (Tom Lane, )
   Re: Caching by Postgres  (Josh Berkus, )
    Re: Caching by Postgres  (Michael Stone, )
   Re: Caching by Postgres  (, )
   Re: Caching by Postgres  (William Yu, )
    Re: Caching by Postgres  (PFC, )
     Re: Caching by Postgres  (Josh Berkus, )
      Re: Caching by Postgres  (PFC, )
     Re: Caching by Postgres  (Gavin Sherry, )
      Re: Caching by Postgres  (Tom Lane, )
       Re: Caching by Postgres  (Gavin Sherry, )
    Re: Caching by Postgres  (Donald Courtney, )
     Re: Caching by Postgres  (Stephen Frost, )
     Re: Caching by Postgres  (, )
      Re: Caching by Postgres  (Alan Stange, )
       Re: Caching by Postgres  (, )
        Re: Caching by Postgres  (Alan Stange, )
         Re: Caching by Postgres  (, )
        Re: Caching by Postgres  (Michael Stone, )
         Re: Caching by Postgres  (, )
       Re: Caching by Postgres  (PFC, )
      Re: Caching by Postgres  (Thomas Ganss, )
     Re: Caching by Postgres  (William Yu, )
 Re: Caching by Postgres  (Chris Browne, )
 Re: Caching by Postgres  (Chris Browne, )

> Josh Berkus has already mentioned this as conventional wisdom as written
> by Oracle. This may also be legacy wisdom. Oracle/Sybase/etc has been
> around for a long time; it was probably a clear performance win way back
> when. Nowadays with how far open-source OS's have advanced, I'd take it
> with a grain of salt and do my own performance analysis. I suspect the
> big vendors wouldn't change their stance even if they knew it was no
> longer true due to the support hassles.

    Reinvent a filesystem... that would be suicidal.

    Now, Hans Reiser has expressed interest on the ReiserFS list in tweaking
his Reiser4 especially for Postgres. In his own words, he wants a "Killer
app for reiser4". Reiser4 will offser transactional semantics via a
special reiser4 syscall, so it might be possible, with a minimum of
changes to postgres (ie maybe just another sync mode besides fsync,
fdatasync et al) to use this. Other interesting details were exposed on
the reiser list, too (ie. a transactional filesystems can give ACID
guarantees to postgres without the need for fsync()).

    Very interesting.


pgsql-performance by date:

From: "Jeffrey W. Baker"
Date:
Subject: Re: Read/Write block sizes
From: Tom Lane
Date:
Subject: Re: Read/Write block sizes