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Re: Constraints for R/O ./data/{base, et al.}

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Don Y wrote:
> Given largely static tables (etc.), how much of ./data
> can I move onto R/O media?  And, which types of operations
> would a user then have to avoid?

As has been mentioned, that is not supported.
For example, every checkpoint changes files in the data directory.

> Loosening constraints a little, how much more could a user
> do if the R/O media was just "very slowly writable" media?

He or she could do everything, DML would be very slow.
The only file that is updated frequently is
$PGDATA/pg_stat_tmp/pgstat.stat, that should be the only impact
on read-only queries.

> Finally, what operations *require* the fastest media updates
> (i.e., "RAM")?

I am not sure if I understand you right, maybe you can clarify
that question.
No operation requires fast media updates.
RAM disks are a bad choice for persistent data.

Yours,
Laurenz Albe 

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Constraints for R/O ./data/{base, et al.} Don Y <nowhere@here.com> - 2011-09-28 08:58 -0700
  Re: Constraints for R/O ./data/{base, et al.} Mladen Gogala <gogala.mladen@gmail.com> - 2011-09-28 18:51 +0000
  Re: Constraints for R/O ./data/{base, et al.} "Laurenz Albe" <invite@spam.to.invalid> - 2011-09-29 09:37 +0200
    Re: Constraints for R/O ./data/{base, et al.} Don Y <nowhere@here.com> - 2011-10-06 22:17 -0700
      Re: Constraints for R/O ./data/{base, et al.} "Laurenz Albe" <invite@spam.to.invalid> - 2011-10-07 10:10 +0200
        Re: Constraints for R/O ./data/{base, et al.} Don Y <nowhere@here.com> - 2011-10-07 11:12 -0700
          Re: Constraints for R/O ./data/{base, et al.} Mladen Gogala <gogala.mladen@gmail.com> - 2011-10-08 05:48 +0000
          Re: Constraints for R/O ./data/{base, et al.} "Laurenz Albe" <invite@spam.to.invalid> - 2011-10-10 16:48 +0200
            Re: Constraints for R/O ./data/{base, et al.} "Laurenz Albe" <invite@spam.to.invalid> - 2011-10-25 12:37 +0200

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