Re: fsync-pgdata-on-recovery tries to write to more files than previously - Mailing list pgsql-hackers

From Stephen Frost
Subject Re: fsync-pgdata-on-recovery tries to write to more files than previously
Date
Msg-id 20150525182302.GS26667@tamriel.snowman.net
Whole thread Raw
In response to Re: fsync-pgdata-on-recovery tries to write to more files than previously  (Andres Freund <andres@anarazel.de>)
List pgsql-hackers
* Andres Freund (andres@anarazel.de) wrote:
> On 2015-05-25 14:14:10 -0400, Stephen Frost wrote:
> > That seems overly complicated, for my 2c at least.  I don't particularly
> > like trying to mess with files that might be rightfully considered "not
> > ours" either.
>
> I'd not consider an fsync to be "messing" with files, especially if
> they're in PGDATA.

I'm not entirely sure I agree.

> > > Additionally we could attempt to fsync with a readonly fd before trying
> > > the read-write fd...
> >
> > Not really sure I see that as helping.
>
> On most OSs, except windows and some obscure unixes, a readonly fd is
> allowed to fsync a file.

I wouldn't have thought otherwise, given that you were suggesting it,
but there's no guarantee we're going to be allowed to read it either, or
even access the directory the symlink points to, etc..
Thanks,
    Stephen

pgsql-hackers by date:

Previous
From: Alvaro Herrera
Date:
Subject: Re: Update README.tuplock?
Next
From: Andres Freund
Date:
Subject: Re: fsync-pgdata-on-recovery tries to write to more files than previously