Обсуждение: can disks be read only?

hi,
  we wish to have a database that is history so we
want to make the disks read only after loading.
would this cause any problems with POSTGRES?  it's on
a linux 6.2 box with POSTGRES 7.0.2.  what we're
looking for here is that if the system crashes we
can do a fast boot and not have the system do an FSCK.

one company bought another and we're going to warehouse
the purchased company's data for reference.  they'll be
no additions to it once loaded.


thanks,
   mikeo

mikeo <mikeo@spectrumtelecorp.com> writes:
>   we wish to have a database that is history so we
> want to make the disks read only after loading.
> would this cause any problems with POSTGRES?

In theory you could do it given that you vacuum the tables
before locking down the files.  (The vacuum is needed to
ensure that on-row commit status bits are up to date.)

In practice you'd likely have problems with the minor detail
that md.c opens everything with O_RDWR privilege requests.
You could probably do a quick hack to try O_RDONLY if
O_RDWR fails...

            regards, tom lane

> >   we wish to have a database that is history so we
> > want to make the disks read only after loading.
> > would this cause any problems with POSTGRES?

You mentioned Linux: try using one of the logging file systems like
reiserfs, which will reduce or eliminate the time now spent in fsck
during boot.

                    - Thomas